diff --git a/debuggerd/Android.bp b/debuggerd/Android.bp
index 439218d..235fdfd 100644
--- a/debuggerd/Android.bp
+++ b/debuggerd/Android.bp
@@ -371,6 +371,11 @@
         },
     },
 
+    sanitize: {
+        memtag_heap: true,
+        memtag_stack: true,
+    },
+
     shared_libs: [
         "libbase",
         "libcutils",
diff --git a/debuggerd/crash_dump.cpp b/debuggerd/crash_dump.cpp
index a23a269..203b485 100644
--- a/debuggerd/crash_dump.cpp
+++ b/debuggerd/crash_dump.cpp
@@ -143,7 +143,7 @@
 }
 
 static bool activity_manager_notify(pid_t pid, int signal, const std::string& amfd_data,
-                                    bool recoverable_gwp_asan_crash) {
+                                    bool recoverable_crash) {
   ATRACE_CALL();
   android::base::unique_fd amfd(socket_local_client(
       "/data/system/ndebugsocket", ANDROID_SOCKET_NAMESPACE_FILESYSTEM, SOCK_STREAM));
@@ -169,7 +169,7 @@
   // Activity Manager protocol:
   //  - 32-bit network-byte-order: pid
   //  - 32-bit network-byte-order: signal number
-  //  - byte: recoverable_gwp_asan_crash
+  //  - byte: recoverable_crash
   //  - bytes: raw text of the dump
   //  - null terminator
 
@@ -185,10 +185,9 @@
     return false;
   }
 
-  uint8_t recoverable_gwp_asan_crash_byte = recoverable_gwp_asan_crash ? 1 : 0;
-  if (!android::base::WriteFully(amfd, &recoverable_gwp_asan_crash_byte,
-                                 sizeof(recoverable_gwp_asan_crash_byte))) {
-    PLOG(ERROR) << "AM recoverable_gwp_asan_crash_byte write failed";
+  uint8_t recoverable_crash_byte = recoverable_crash ? 1 : 0;
+  if (!android::base::WriteFully(amfd, &recoverable_crash_byte, sizeof(recoverable_crash_byte))) {
+    PLOG(ERROR) << "AM recoverable_crash_byte write failed";
     return false;
   }
 
@@ -280,11 +279,11 @@
 
 static void ReadCrashInfo(unique_fd& fd, siginfo_t* siginfo,
                           std::unique_ptr<unwindstack::Regs>* regs, ProcessInfo* process_info,
-                          bool* recoverable_gwp_asan_crash) {
+                          bool* recoverable_crash) {
   std::aligned_storage<sizeof(CrashInfo) + 1, alignof(CrashInfo)>::type buf;
   CrashInfo* crash_info = reinterpret_cast<CrashInfo*>(&buf);
   ssize_t rc = TEMP_FAILURE_RETRY(read(fd.get(), &buf, sizeof(buf)));
-  *recoverable_gwp_asan_crash = false;
+  *recoverable_crash = false;
   if (rc == -1) {
     PLOG(FATAL) << "failed to read target ucontext";
   } else {
@@ -321,7 +320,7 @@
       process_info->scudo_region_info = crash_info->data.d.scudo_region_info;
       process_info->scudo_ring_buffer = crash_info->data.d.scudo_ring_buffer;
       process_info->scudo_ring_buffer_size = crash_info->data.d.scudo_ring_buffer_size;
-      *recoverable_gwp_asan_crash = crash_info->data.d.recoverable_gwp_asan_crash;
+      *recoverable_crash = crash_info->data.d.recoverable_crash;
       process_info->crash_detail_page = crash_info->data.d.crash_detail_page;
       FALLTHROUGH_INTENDED;
     case 1:
@@ -487,7 +486,7 @@
   std::map<pid_t, ThreadInfo> thread_info;
   siginfo_t siginfo;
   std::string error;
-  bool recoverable_gwp_asan_crash = false;
+  bool recoverable_crash = false;
 
   {
     ATRACE_NAME("ptrace");
@@ -539,8 +538,7 @@
 
       if (thread == g_target_thread) {
         // Read the thread's registers along with the rest of the crash info out of the pipe.
-        ReadCrashInfo(input_pipe, &siginfo, &info.registers, &process_info,
-                      &recoverable_gwp_asan_crash);
+        ReadCrashInfo(input_pipe, &siginfo, &info.registers, &process_info, &recoverable_crash);
         info.siginfo = &siginfo;
         info.signo = info.siginfo->si_signo;
 
@@ -670,7 +668,7 @@
   if (fatal_signal) {
     // Don't try to notify ActivityManager if it just crashed, or we might hang until timeout.
     if (thread_info[target_process].thread_name != "system_server") {
-      activity_manager_notify(target_process, signo, amfd_data, recoverable_gwp_asan_crash);
+      activity_manager_notify(target_process, signo, amfd_data, recoverable_crash);
     }
   }
 
diff --git a/debuggerd/debuggerd_test.cpp b/debuggerd/debuggerd_test.cpp
index f396b1d..526e2ca 100644
--- a/debuggerd/debuggerd_test.cpp
+++ b/debuggerd/debuggerd_test.cpp
@@ -21,6 +21,7 @@
 #include <linux/prctl.h>
 #include <malloc.h>
 #include <pthread.h>
+#include <setjmp.h>
 #include <stdlib.h>
 #include <sys/capability.h>
 #include <sys/mman.h>
@@ -601,6 +602,54 @@
 #endif
 }
 
+__attribute__((noinline)) void mte_illegal_setjmp_helper(jmp_buf& jump_buf) {
+  // This frame is at least 8 bytes for storing and restoring the LR before the
+  // setjmp below. So this can never get an empty stack frame, even if we omit
+  // the frame pointer. So, the SP of this is always less (numerically) than the
+  // calling function frame.
+  setjmp(jump_buf);
+}
+
+TEST_F(CrasherTest, mte_illegal_setjmp) {
+  // This setjmp is illegal because it jumps back into a function that already returned.
+  // Quoting man 3 setjmp:
+  //     If the function which called setjmp() returns before longjmp() is
+  //     called, the behavior is undefined.  Some kind of subtle or
+  //     unsubtle chaos is sure to result.
+  // https://man7.org/linux/man-pages/man3/longjmp.3.html
+#if defined(__aarch64__)
+  if (!mte_supported()) {
+    GTEST_SKIP() << "Requires MTE";
+  }
+
+  int intercept_result;
+  unique_fd output_fd;
+  StartProcess([&]() {
+    SetTagCheckingLevelSync();
+    jmp_buf jump_buf;
+    mte_illegal_setjmp_helper(jump_buf);
+    longjmp(jump_buf, 1);
+  });
+
+  StartIntercept(&output_fd);
+  FinishCrasher();
+  AssertDeath(SIGABRT);
+  FinishIntercept(&intercept_result);
+
+  ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
+
+  std::string result;
+  ConsumeFd(std::move(output_fd), &result);
+
+  // In our test-case, we have a NEGATIVE stack adjustment, which is being
+  // interpreted as unsigned integer, and thus is "too large".
+  // TODO(fmayer): fix the error message for this
+  ASSERT_MATCH(result, R"(memtag_handle_longjmp: stack adjustment too large)");
+#else
+  GTEST_SKIP() << "Requires aarch64";
+#endif
+}
+
 TEST_F(CrasherTest, mte_async) {
 #if defined(__aarch64__)
   if (!mte_supported()) {
@@ -2647,7 +2696,7 @@
   match_str += format_full_pointer(crash_uptr);
   ASSERT_MATCH(result, match_str);
 
-  ASSERT_MATCH(result, R"(\nmemory map \(.*\): \(fault address prefixed with --->)\n)");
+  ASSERT_MATCH(result, R"(\nmemory map \(.*\): \(fault address prefixed with --->\)\n)");
 
   // Verifies that the fault address error message is at the end of the
   // maps section. To do this, the check below looks for the start of the
@@ -2699,7 +2748,7 @@
   match_str += format_full_pointer(reinterpret_cast<uintptr_t>(middle_ptr));
   ASSERT_MATCH(result, match_str);
 
-  ASSERT_MATCH(result, R"(\nmemory map \(.*\): \(fault address prefixed with --->)\n)");
+  ASSERT_MATCH(result, R"(\nmemory map \(.*\): \(fault address prefixed with --->\)\n)");
 
   match_str = android::base::StringPrintf(
       R"(    %s.*\n--->Fault address falls at %s between mapped regions\n    %s)",
@@ -2737,7 +2786,7 @@
   match_str += format_full_pointer(reinterpret_cast<uintptr_t>(ptr));
   ASSERT_MATCH(result, match_str);
 
-  ASSERT_MATCH(result, R"(\nmemory map \(.*\): \(fault address prefixed with --->)\n)");
+  ASSERT_MATCH(result, R"(\nmemory map \(.*\): \(fault address prefixed with --->\)\n)");
 
   match_str = android::base::StringPrintf(R"(\n--->%s.*\n)", format_pointer(ptr).c_str());
   ASSERT_MATCH(result, match_str);
diff --git a/debuggerd/handler/debuggerd_handler.cpp b/debuggerd/handler/debuggerd_handler.cpp
index 141723b..25031bf 100644
--- a/debuggerd/handler/debuggerd_handler.cpp
+++ b/debuggerd/handler/debuggerd_handler.cpp
@@ -275,10 +275,6 @@
   }
 }
 
-static pid_t __fork() {
-  return clone(nullptr, nullptr, 0, nullptr);
-}
-
 // Double-clone, with CLONE_FILES to share the file descriptor table for kcmp validation.
 // Returns 0 in the orphaned child, the pid of the orphan in the original process, or -1 on failure.
 static void create_vm_process() {
@@ -396,7 +392,7 @@
     ASSERT_SAME_OFFSET(scudo_ring_buffer, scudo_ring_buffer);
     ASSERT_SAME_OFFSET(scudo_ring_buffer_size, scudo_ring_buffer_size);
     ASSERT_SAME_OFFSET(scudo_stack_depot_size, scudo_stack_depot_size);
-    ASSERT_SAME_OFFSET(recoverable_gwp_asan_crash, recoverable_gwp_asan_crash);
+    ASSERT_SAME_OFFSET(recoverable_crash, recoverable_crash);
     ASSERT_SAME_OFFSET(crash_detail_page, crash_detail_page);
 #undef ASSERT_SAME_OFFSET
 
@@ -426,7 +422,7 @@
   }
 
   // Don't use fork(2) to avoid calling pthread_atfork handlers.
-  pid_t crash_dump_pid = __fork();
+  pid_t crash_dump_pid = _Fork();
   if (crash_dump_pid == -1) {
     async_safe_format_log(ANDROID_LOG_FATAL, "libc",
                           "failed to fork in debuggerd signal handler: %s", strerror(errno));
@@ -573,6 +569,7 @@
   }
 
   gwp_asan_callbacks_t gwp_asan_callbacks = {};
+  bool recoverable_gwp_asan_crash = false;
   if (g_callbacks.get_gwp_asan_callbacks != nullptr) {
     // GWP-ASan catches use-after-free and heap-buffer-overflow by using PROT_NONE
     // guard pages, which lead to SEGV. Normally, debuggerd prints a bug report
@@ -587,10 +584,30 @@
         gwp_asan_callbacks.debuggerd_gwp_asan_post_crash_report &&
         gwp_asan_callbacks.debuggerd_needs_gwp_asan_recovery(info->si_addr)) {
       gwp_asan_callbacks.debuggerd_gwp_asan_pre_crash_report(info->si_addr);
-      process_info.recoverable_gwp_asan_crash = true;
+      recoverable_gwp_asan_crash = true;
+      process_info.recoverable_crash = true;
     }
   }
 
+  if (info->si_signo == SIGSEGV &&
+      (info->si_code == SEGV_MTESERR || info->si_code == SEGV_MTEAERR) && is_permissive_mte()) {
+    process_info.recoverable_crash = true;
+    // If we are in permissive MTE mode, we do not crash, but instead disable MTE on this thread,
+    // and then let the failing instruction be retried. The second time should work (except
+    // if there is another non-MTE fault).
+    int tagged_addr_ctrl = prctl(PR_GET_TAGGED_ADDR_CTRL, 0, 0, 0, 0);
+    if (tagged_addr_ctrl < 0) {
+      fatal_errno("failed to PR_GET_TAGGED_ADDR_CTRL");
+    }
+    tagged_addr_ctrl = (tagged_addr_ctrl & ~PR_MTE_TCF_MASK) | PR_MTE_TCF_NONE;
+    if (prctl(PR_SET_TAGGED_ADDR_CTRL, tagged_addr_ctrl, 0, 0, 0) < 0) {
+      fatal_errno("failed to PR_SET_TAGGED_ADDR_CTRL");
+    }
+    async_safe_format_log(ANDROID_LOG_ERROR, "libc",
+                          "MTE ERROR DETECTED BUT RUNNING IN PERMISSIVE MODE. CONTINUING.");
+    pthread_mutex_unlock(&crash_mutex);
+  }
+
   // If sival_int is ~0, it means that the fallback handler has been called
   // once before and this function is being called again to dump the stack
   // of a specific thread. It is possible that the prctl call might return 1,
@@ -602,7 +619,7 @@
     // you can only set NO_NEW_PRIVS to 1, and the effect should be at worst a single missing
     // ANR trace.
     debuggerd_fallback_handler(info, ucontext, process_info.abort_msg);
-    if (no_new_privs && process_info.recoverable_gwp_asan_crash) {
+    if (no_new_privs && recoverable_gwp_asan_crash) {
       gwp_asan_callbacks.debuggerd_gwp_asan_post_crash_report(info->si_addr);
       return;
     }
@@ -679,29 +696,14 @@
     // If the signal is fatal, don't unlock the mutex to prevent other crashing threads from
     // starting to dump right before our death.
     pthread_mutex_unlock(&crash_mutex);
-  } else if (process_info.recoverable_gwp_asan_crash) {
-    gwp_asan_callbacks.debuggerd_gwp_asan_post_crash_report(info->si_addr);
+  } else if (process_info.recoverable_crash) {
+    if (recoverable_gwp_asan_crash) {
+      gwp_asan_callbacks.debuggerd_gwp_asan_post_crash_report(info->si_addr);
+    }
     pthread_mutex_unlock(&crash_mutex);
   }
 #ifdef __aarch64__
-  else if (info->si_signo == SIGSEGV &&
-           (info->si_code == SEGV_MTESERR || info->si_code == SEGV_MTEAERR) &&
-           is_permissive_mte()) {
-    // If we are in permissive MTE mode, we do not crash, but instead disable MTE on this thread,
-    // and then let the failing instruction be retried. The second time should work (except
-    // if there is another non-MTE fault).
-    int tagged_addr_ctrl = prctl(PR_GET_TAGGED_ADDR_CTRL, 0, 0, 0, 0);
-    if (tagged_addr_ctrl < 0) {
-      fatal_errno("failed to PR_GET_TAGGED_ADDR_CTRL");
-    }
-    tagged_addr_ctrl = (tagged_addr_ctrl & ~PR_MTE_TCF_MASK) | PR_MTE_TCF_NONE;
-    if (prctl(PR_SET_TAGGED_ADDR_CTRL, tagged_addr_ctrl, 0, 0, 0) < 0) {
-      fatal_errno("failed to PR_SET_TAGGED_ADDR_CTRL");
-    }
-    async_safe_format_log(ANDROID_LOG_ERROR, "libc",
-                          "MTE ERROR DETECTED BUT RUNNING IN PERMISSIVE MODE. CONTINUING.");
-    pthread_mutex_unlock(&crash_mutex);
-  } else if (info->si_signo == SIGSEGV && info->si_code == SEGV_MTEAERR && getppid() == 1) {
+  else if (info->si_signo == SIGSEGV && info->si_code == SEGV_MTEAERR && getppid() == 1) {
     // Back channel to init (see system/core/init/service.cpp) to signal that
     // this process crashed due to an ASYNC MTE fault and should be considered
     // for upgrade to SYNC mode. We are re-using the ART profiler signal, which
@@ -761,18 +763,7 @@
   debuggerd_register_handlers(&action);
 }
 
-// When debuggerd's signal handler is the first handler called, it's great at
-// handling the recoverable GWP-ASan mode. For apps, sigchain (from libart) is
-// always the first signal handler, and so the following function is what
-// sigchain must call before processing the signal. This allows for processing
-// of a potentially recoverable GWP-ASan crash. If the signal requires GWP-ASan
-// recovery, then dump a report (via the regular debuggerd hanndler), and patch
-// up the allocator, and allow the process to continue (indicated by returning
-// 'true'). If the crash has nothing to do with GWP-ASan, or recovery isn't
-// possible, return 'false'.
-bool debuggerd_handle_signal(int signal_number, siginfo_t* info, void* context) {
-  if (signal_number != SIGSEGV || !signal_has_si_addr(info)) return false;
-
+bool debuggerd_handle_gwp_asan_signal(int signal_number, siginfo_t* info, void* context) {
   if (g_callbacks.get_gwp_asan_callbacks == nullptr) return false;
   gwp_asan_callbacks_t gwp_asan_callbacks = g_callbacks.get_gwp_asan_callbacks();
   if (gwp_asan_callbacks.debuggerd_needs_gwp_asan_recovery == nullptr ||
@@ -810,3 +801,33 @@
   pthread_mutex_unlock(&first_crash_mutex);
   return true;
 }
+
+// When debuggerd's signal handler is the first handler called, it's great at
+// handling the recoverable GWP-ASan and permissive MTE modes. For apps,
+// sigchain (from libart) is always the first signal handler, and so the
+// following function is what sigchain must call before processing the signal.
+// This allows for processing of a potentially recoverable GWP-ASan or MTE
+// crash. If the signal requires recovery, then dump a report (via the regular
+// debuggerd hanndler), and patch up the allocator (in the case of GWP-ASan) or
+// disable MTE on the thread, and allow the process to continue (indicated by
+// returning 'true'). If the crash has nothing to do with GWP-ASan/MTE, or
+// recovery isn't possible, return 'false'.
+bool debuggerd_handle_signal(int signal_number, siginfo_t* info, void* context) {
+  if (signal_number != SIGSEGV) return false;
+  if (info->si_code == SEGV_MTEAERR || info->si_code == SEGV_MTESERR) {
+    if (!is_permissive_mte()) return false;
+    // Because permissive MTE disables MTE for the entire thread, we're less
+    // worried about getting a whole bunch of crashes in a row. ActivityManager
+    // doesn't like multiple native crashes for an app in a short period of time
+    // (see the comment about recoverable GWP-ASan in
+    // `debuggerd_handle_gwp_asan_signal`), but that shouldn't happen if MTE is
+    // disabled for the entire thread. This might need to be changed if there's
+    // some low-hanging bug that happens across multiple threads in quick
+    // succession.
+    debuggerd_signal_handler(signal_number, info, context);
+    return true;
+  }
+
+  if (!signal_has_si_addr(info)) return false;
+  return debuggerd_handle_gwp_asan_signal(signal_number, info, context);
+}
diff --git a/debuggerd/include/debuggerd/handler.h b/debuggerd/include/debuggerd/handler.h
index c18cf6e..954f049 100644
--- a/debuggerd/include/debuggerd/handler.h
+++ b/debuggerd/include/debuggerd/handler.h
@@ -47,7 +47,7 @@
   const char* scudo_ring_buffer;
   size_t scudo_ring_buffer_size;
   size_t scudo_stack_depot_size;
-  bool recoverable_gwp_asan_crash;
+  bool recoverable_crash;
   struct crash_detail_page_t* crash_detail_page;
 };
 
diff --git a/debuggerd/protocol.h b/debuggerd/protocol.h
index d3fc15e..9af7377 100644
--- a/debuggerd/protocol.h
+++ b/debuggerd/protocol.h
@@ -100,7 +100,7 @@
   uintptr_t scudo_ring_buffer;
   size_t scudo_ring_buffer_size;
   size_t scudo_stack_depot_size;
-  bool recoverable_gwp_asan_crash;
+  bool recoverable_crash;
   uintptr_t crash_detail_page;
 };
 
diff --git a/debuggerd/tombstoned/tombstoned.cpp b/debuggerd/tombstoned/tombstoned.cpp
index e2a67a2..fa67d46 100644
--- a/debuggerd/tombstoned/tombstoned.cpp
+++ b/debuggerd/tombstoned/tombstoned.cpp
@@ -96,7 +96,7 @@
 class CrashQueue {
  public:
   CrashQueue(const std::string& dir_path, const std::string& file_name_prefix, size_t max_artifacts,
-             size_t max_concurrent_dumps, bool supports_proto)
+             size_t max_concurrent_dumps, bool supports_proto, bool world_readable)
       : file_name_prefix_(file_name_prefix),
         dir_path_(dir_path),
         dir_fd_(open(dir_path.c_str(), O_DIRECTORY | O_RDONLY | O_CLOEXEC)),
@@ -104,7 +104,8 @@
         next_artifact_(0),
         max_concurrent_dumps_(max_concurrent_dumps),
         num_concurrent_dumps_(0),
-        supports_proto_(supports_proto) {
+        supports_proto_(supports_proto),
+        world_readable_(world_readable) {
     if (dir_fd_ == -1) {
       PLOG(FATAL) << "failed to open directory: " << dir_path;
     }
@@ -127,14 +128,16 @@
   static CrashQueue* for_tombstones() {
     static CrashQueue queue("/data/tombstones", "tombstone_" /* file_name_prefix */,
                             GetIntProperty("tombstoned.max_tombstone_count", 32),
-                            1 /* max_concurrent_dumps */, true /* supports_proto */);
+                            1 /* max_concurrent_dumps */, true /* supports_proto */,
+                            true /* world_readable */);
     return &queue;
   }
 
   static CrashQueue* for_anrs() {
     static CrashQueue queue("/data/anr", "trace_" /* file_name_prefix */,
                             GetIntProperty("tombstoned.max_anr_count", 64),
-                            4 /* max_concurrent_dumps */, false /* supports_proto */);
+                            4 /* max_concurrent_dumps */, false /* supports_proto */,
+                            false /* world_readable */);
     return &queue;
   }
 
@@ -147,10 +150,12 @@
       PLOG(FATAL) << "failed to create temporary tombstone in " << dir_path_;
     }
 
-    // We need to fchmodat after creating to avoid getting the umask applied.
-    std::string fd_path = StringPrintf("/proc/self/fd/%d", result.fd.get());
-    if (fchmodat(dir_fd_, fd_path.c_str(), 0664, 0) != 0) {
-      PLOG(ERROR) << "Failed to make tombstone world-readable";
+    if (world_readable_) {
+      // We need to fchmodat after creating to avoid getting the umask applied.
+      std::string fd_path = StringPrintf("/proc/self/fd/%d", result.fd.get());
+      if (fchmodat(dir_fd_, fd_path.c_str(), 0664, 0) != 0) {
+        PLOG(ERROR) << "Failed to make tombstone world-readable";
+      }
     }
 
     return std::move(result);
@@ -262,6 +267,7 @@
   size_t num_concurrent_dumps_;
 
   bool supports_proto_;
+  bool world_readable_;
 
   std::deque<std::unique_ptr<Crash>> queued_requests_;
 
@@ -450,6 +456,14 @@
 
   CrashArtifactPaths paths = queue->get_next_artifact_paths();
 
+  if (crash->output.proto && crash->output.proto->fd != -1) {
+    if (!paths.proto) {
+      LOG(ERROR) << "missing path for proto tombstone";
+    } else {
+      rename_tombstone_fd(crash->output.proto->fd, queue->dir_fd(), *paths.proto);
+    }
+  }
+
   if (rename_tombstone_fd(crash->output.text.fd, queue->dir_fd(), paths.text)) {
     if (crash->crash_type == kDebuggerdJavaBacktrace) {
       LOG(ERROR) << "Traces for pid " << crash->crash_pid << " written to: " << paths.text;
@@ -460,14 +474,6 @@
       LOG(ERROR) << "Tombstone written to: " << paths.text;
     }
   }
-
-  if (crash->output.proto && crash->output.proto->fd != -1) {
-    if (!paths.proto) {
-      LOG(ERROR) << "missing path for proto tombstone";
-    } else {
-      rename_tombstone_fd(crash->output.proto->fd, queue->dir_fd(), *paths.proto);
-    }
-  }
 }
 
 static void crash_completed_cb(evutil_socket_t sockfd, short ev, void* arg) {
diff --git a/fs_mgr/TEST_MAPPING b/fs_mgr/TEST_MAPPING
index 1989a5c..32e8b88 100644
--- a/fs_mgr/TEST_MAPPING
+++ b/fs_mgr/TEST_MAPPING
@@ -25,8 +25,6 @@
     {
       "name": "vab_legacy_tests"
     },
-    // TODO(b/279009697):
-    //{"name": "vabc_legacy_tests"},
     {
       "name": "cow_api_test"
     },
@@ -44,8 +42,6 @@
     {
       "name": "vab_legacy_tests"
     },
-    // TODO(b/279009697):
-    //{"name": "vabc_legacy_tests"}
     {
       "name": "snapuserd_test"
     }
diff --git a/fs_mgr/libdm/dm.cpp b/fs_mgr/libdm/dm.cpp
index e261aa3..fee67fdf 100644
--- a/fs_mgr/libdm/dm.cpp
+++ b/fs_mgr/libdm/dm.cpp
@@ -39,6 +39,9 @@
 #ifndef DM_DEFERRED_REMOVE
 #define DM_DEFERRED_REMOVE (1 << 17)
 #endif
+#ifndef DM_IMA_MEASUREMENT_FLAG
+#define DM_IMA_MEASUREMENT_FLAG (1 << 19)
+#endif
 
 namespace android {
 namespace dm {
@@ -540,6 +543,10 @@
     return GetTable(name, 0, table);
 }
 
+bool DeviceMapper::GetTableStatusIma(const std::string& name, std::vector<TargetInfo>* table) {
+    return GetTable(name, DM_IMA_MEASUREMENT_FLAG, table);
+}
+
 bool DeviceMapper::GetTableInfo(const std::string& name, std::vector<TargetInfo>* table) {
     return GetTable(name, DM_STATUS_TABLE_FLAG, table);
 }
diff --git a/fs_mgr/libdm/include/libdm/dm.h b/fs_mgr/libdm/include/libdm/dm.h
index 22c475f..fa97653 100644
--- a/fs_mgr/libdm/include/libdm/dm.h
+++ b/fs_mgr/libdm/include/libdm/dm.h
@@ -78,6 +78,7 @@
     virtual bool LoadTable(const std::string& name, const DmTable& table) = 0;
     virtual bool GetTableInfo(const std::string& name, std::vector<TargetInfo>* table) = 0;
     virtual bool GetTableStatus(const std::string& name, std::vector<TargetInfo>* table) = 0;
+    virtual bool GetTableStatusIma(const std::string& name, std::vector<TargetInfo>* table) = 0;
     virtual bool GetDmDevicePathByName(const std::string& name, std::string* path) = 0;
     virtual bool GetDeviceString(const std::string& name, std::string* dev) = 0;
     virtual bool DeleteDeviceIfExists(const std::string& name) = 0;
@@ -267,6 +268,12 @@
     // false.
     bool GetTableStatus(const std::string& name, std::vector<TargetInfo>* table) override;
 
+    // Query the status of a table, given a device name. The output vector will
+    // contain IMA TargetInfo for each target in the table. If the device does
+    // not exist, or there were too many targets, the call will fail and return
+    // false.
+    bool GetTableStatusIma(const std::string& name, std::vector<TargetInfo>* table) override;
+
     // Identical to GetTableStatus, except also retrives the active table for the device
     // mapper device from the kernel.
     bool GetTableInfo(const std::string& name, std::vector<TargetInfo>* table) override;
diff --git a/fs_mgr/liblp/fuzzer/liblp_builder_fuzzer.cpp b/fs_mgr/liblp/fuzzer/liblp_builder_fuzzer.cpp
index 7f09ac8..162c9fc 100644
--- a/fs_mgr/liblp/fuzzer/liblp_builder_fuzzer.cpp
+++ b/fs_mgr/liblp/fuzzer/liblp_builder_fuzzer.cpp
@@ -28,7 +28,7 @@
 static constexpr uint64_t kBlockDeviceInfoSize = 1024 * 1024;
 static constexpr uint64_t kValidBlockDeviceInfoSize = 8_GiB;
 static constexpr uint64_t kValidMaxGroupSize = 40960;
-static constexpr uint64_t kMinBlockDevValue = 0;
+static constexpr uint64_t kMinBlockDevValue = 1;
 static constexpr uint64_t kMaxBlockDevValue = 100000;
 static constexpr uint64_t kMinSectorValue = 1;
 static constexpr uint64_t kMaxSectorValue = 1000000;
@@ -149,12 +149,16 @@
 
 void BuilderFuzzer::setupBuilder(string superBlockDeviceName) {
     uint64_t blockDeviceInfoSize =
-            mFdp.ConsumeBool() ? mFdp.ConsumeIntegral<uint64_t>() : kValidBlockDeviceInfoSize;
+            mFdp.ConsumeBool()
+                    ? mFdp.ConsumeIntegralInRange<uint64_t>(kMinBlockDevValue, kMaxBlockDevValue)
+                    : kValidBlockDeviceInfoSize;
     uint32_t alignment = mFdp.ConsumeBool() ? mFdp.ConsumeIntegral<uint32_t>() : kValidAlignment;
     uint32_t alignmentOffset =
             mFdp.ConsumeBool() ? mFdp.ConsumeIntegral<uint32_t>() : kValidAlignmentOffset;
-    uint32_t logicalBlockSize =
-            mFdp.ConsumeBool() ? mFdp.ConsumeIntegral<uint32_t>() : kValidLogicalBlockSize;
+    uint32_t logicalBlockSize = mFdp.ConsumeBool() ? mFdp.ConsumeIntegralInRange<uint32_t>(
+                                                             kMinBlockDevValue, kMaxBlockDevValue)
+                                                   : kValidLogicalBlockSize;
+
     BlockDeviceInfo super(superBlockDeviceName, blockDeviceInfoSize, alignment, alignmentOffset,
                           logicalBlockSize);
     mBlockDevices.push_back(super);
@@ -176,13 +180,16 @@
             mFdp.ConsumeBool() ? kDeviceInfoName : mFdp.ConsumeRandomLengthString(kMaxBytes);
     BlockDeviceInfo changePartitionDeviceInfo(
             changePartitionDeviceInfoName,
-            mFdp.ConsumeBool() ? mFdp.ConsumeIntegral<uint64_t>() : kBlockDeviceInfoSize /* size */,
+            mFdp.ConsumeBool()
+                    ? mFdp.ConsumeIntegralInRange<uint64_t>(kMinBlockDevValue, kMaxBlockDevValue)
+                    : kBlockDeviceInfoSize /* size */,
             mFdp.ConsumeBool() ? mFdp.ConsumeIntegral<uint32_t>()
                                : kZeroAlignmentOffset /* alignment */,
             mFdp.ConsumeBool() ? mFdp.ConsumeIntegral<uint32_t>()
                                : kZeroAlignmentOffset /* alignment_offset */,
-            mFdp.ConsumeBool() ? mFdp.ConsumeIntegral<uint32_t>()
-                               : kValidLogicalBlockSize /* logical_block_size */);
+            mFdp.ConsumeBool()
+                    ? mFdp.ConsumeIntegralInRange<uint32_t>(kMinBlockDevValue, kMaxBlockDevValue)
+                    : kValidLogicalBlockSize);
     mBlockDevices.push_back(changePartitionDeviceInfo);
 }
 
diff --git a/fs_mgr/libsnapshot/Android.bp b/fs_mgr/libsnapshot/Android.bp
index 5ceaf28..914b4a6 100644
--- a/fs_mgr/libsnapshot/Android.bp
+++ b/fs_mgr/libsnapshot/Android.bp
@@ -322,24 +322,6 @@
 }
 
 cc_test {
-    name: "vabc_legacy_tests",
-    defaults: [
-        "libsnapshot_test_defaults",
-        "libsnapshot_hal_deps",
-    ],
-    cppflags: [
-        "-DLIBSNAPSHOT_TEST_VABC_LEGACY",
-    ],
-    test_suites: [
-        "device-tests",
-    ],
-    test_options: {
-        // Legacy VABC launched in Android S.
-        min_shipping_api_level: 31,
-    },
-}
-
-cc_test {
     name: "vts_ota_config_test",
     srcs: [
         "vts_ota_config_test.cpp",
diff --git a/fs_mgr/libsnapshot/android/snapshot/snapshot.proto b/fs_mgr/libsnapshot/android/snapshot/snapshot.proto
index f2f7fc1..076a918 100644
--- a/fs_mgr/libsnapshot/android/snapshot/snapshot.proto
+++ b/fs_mgr/libsnapshot/android/snapshot/snapshot.proto
@@ -212,6 +212,9 @@
 
     // io_uring support
     bool io_uring_enabled = 10;
+
+    // legacy dm-snapshot based snapuserd
+    bool legacy_snapuserd = 11;
 }
 
 // Next: 10
diff --git a/fs_mgr/libsnapshot/include/libsnapshot/cow_writer.h b/fs_mgr/libsnapshot/include/libsnapshot/cow_writer.h
index 651083f..2c6eefb 100644
--- a/fs_mgr/libsnapshot/include/libsnapshot/cow_writer.h
+++ b/fs_mgr/libsnapshot/include/libsnapshot/cow_writer.h
@@ -45,7 +45,7 @@
     std::optional<uint64_t> max_blocks;
 
     // Number of CowOperations in a cluster. 0 for no clustering. Cannot be 1.
-    uint32_t cluster_ops = 200;
+    uint32_t cluster_ops = 1024;
 
     bool scratch_space = true;
 
diff --git a/fs_mgr/libsnapshot/include/libsnapshot/snapshot.h b/fs_mgr/libsnapshot/include/libsnapshot/snapshot.h
index d102863..3ccc3db 100644
--- a/fs_mgr/libsnapshot/include/libsnapshot/snapshot.h
+++ b/fs_mgr/libsnapshot/include/libsnapshot/snapshot.h
@@ -829,6 +829,9 @@
     // Set read-ahead size during OTA
     void SetReadAheadSize(const std::string& entry_block_device, off64_t size_kb);
 
+    // Returns true post OTA reboot if legacy snapuserd is required
+    bool IsLegacySnapuserdPostReboot();
+
     android::dm::IDeviceMapper& dm_;
     std::unique_ptr<IDeviceInfo> device_;
     std::string metadata_dir_;
@@ -839,6 +842,7 @@
     std::unique_ptr<SnapuserdClient> snapuserd_client_;
     std::unique_ptr<LpMetadata> old_partition_metadata_;
     std::optional<bool> is_snapshot_userspace_;
+    std::optional<bool> is_legacy_snapuserd_;
 };
 
 }  // namespace snapshot
diff --git a/fs_mgr/libsnapshot/include_test/libsnapshot/test_helpers.h b/fs_mgr/libsnapshot/include_test/libsnapshot/test_helpers.h
index 5e9f049..90813fe 100644
--- a/fs_mgr/libsnapshot/include_test/libsnapshot/test_helpers.h
+++ b/fs_mgr/libsnapshot/include_test/libsnapshot/test_helpers.h
@@ -155,6 +155,9 @@
     virtual bool GetTableStatus(const std::string& name, std::vector<TargetInfo>* table) {
         return impl_.GetTableStatus(name, table);
     }
+    virtual bool GetTableStatusIma(const std::string& name, std::vector<TargetInfo>* table) {
+        return impl_.GetTableStatusIma(name, table);
+    }
     virtual bool GetDmDevicePathByName(const std::string& name, std::string* path) {
         return impl_.GetDmDevicePathByName(name, path);
     }
diff --git a/fs_mgr/libsnapshot/libsnapshot_cow/test_v3.cpp b/fs_mgr/libsnapshot/libsnapshot_cow/test_v3.cpp
index 2021348..4456b26 100644
--- a/fs_mgr/libsnapshot/libsnapshot_cow/test_v3.cpp
+++ b/fs_mgr/libsnapshot/libsnapshot_cow/test_v3.cpp
@@ -209,6 +209,48 @@
     ASSERT_EQ(sink, data);
 }
 
+TEST_F(CowTestV3, BigReplaceOp) {
+    CowOptions options;
+    options.op_count_max = 10000;
+    options.batch_write = true;
+    options.cluster_ops = 2048;
+
+    auto writer = CreateCowWriter(3, options, GetCowFd());
+    std::string data = "This is some data, believe it";
+    data.resize(options.block_size * 4096, '\0');
+    for (int i = 0; i < data.size(); i++) {
+        data[i] = static_cast<char>('A' + i / options.block_size);
+    }
+    ASSERT_TRUE(writer->AddRawBlocks(5, data.data(), data.size()));
+    ASSERT_TRUE(writer->Finalize());
+
+    CowReader reader;
+    ASSERT_TRUE(reader.Parse(cow_->fd));
+
+    const auto& header = reader.header_v3();
+    ASSERT_EQ(header.op_count, 4096);
+
+    auto iter = reader.GetOpIter();
+    ASSERT_NE(iter, nullptr);
+    ASSERT_FALSE(iter->AtEnd());
+
+    size_t i = 0;
+
+    while (!iter->AtEnd()) {
+        auto op = iter->Get();
+        std::string sink(options.block_size, '\0');
+        ASSERT_EQ(op->type(), kCowReplaceOp);
+        ASSERT_EQ(op->data_length, options.block_size);
+        ASSERT_EQ(op->new_block, 5 + i);
+        ASSERT_TRUE(ReadData(reader, op, sink.data(), options.block_size));
+        ASSERT_EQ(std::string_view(sink),
+                  std::string_view(data).substr(i * options.block_size, options.block_size))
+                << " readback data for " << i << "th block does not match";
+        iter->Next();
+        i++;
+    }
+}
+
 TEST_F(CowTestV3, ConsecutiveReplaceOp) {
     CowOptions options;
     options.op_count_max = 20;
diff --git a/fs_mgr/libsnapshot/libsnapshot_cow/writer_v3.cpp b/fs_mgr/libsnapshot/libsnapshot_cow/writer_v3.cpp
index de2e528..73deafb 100644
--- a/fs_mgr/libsnapshot/libsnapshot_cow/writer_v3.cpp
+++ b/fs_mgr/libsnapshot/libsnapshot_cow/writer_v3.cpp
@@ -173,7 +173,7 @@
         batch_size_ = std::max<size_t>(options_.cluster_ops, 1);
         data_vec_.reserve(batch_size_);
         cached_data_.reserve(batch_size_);
-        cached_ops_.reserve(batch_size_);
+        cached_ops_.reserve(batch_size_ * kNonDataOpBufferSize);
     }
 
     if (batch_size_ > 1) {
@@ -214,15 +214,6 @@
             return false;
         }
     }
-
-    // TODO: b/322279333
-    // Set compression factor to 4k during estimation.
-    // Once COW estimator is ready to support variable
-    // block size, this check has to be removed.
-    if (IsEstimating()) {
-        header_.max_compression_size = header_.block_size;
-    }
-
     return true;
 }
 
@@ -310,6 +301,14 @@
     return true;
 }
 
+size_t CowWriterV3::CachedDataSize() const {
+    size_t size = 0;
+    for (const auto& i : cached_data_) {
+        size += i.size();
+    }
+    return size;
+}
+
 bool CowWriterV3::EmitCopy(uint64_t new_block, uint64_t old_block, uint64_t num_blocks) {
     if (!CheckOpCount(num_blocks)) {
         return false;
@@ -342,7 +341,8 @@
     // Allow bigger batch sizes for ops without data. A single CowOperationV3
     // struct uses 14 bytes of memory, even if we cache 200 * 16 ops in memory,
     // it's only ~44K.
-    return cached_data_.size() >= batch_size_ || cached_ops_.size() >= batch_size_ * 16;
+    return CachedDataSize() >= batch_size_ * header_.block_size ||
+           cached_ops_.size() >= batch_size_ * kNonDataOpBufferSize;
 }
 
 bool CowWriterV3::ConstructCowOpCompressedBuffers(uint64_t new_block_start, const void* data,
@@ -396,13 +396,13 @@
         return false;
     }
     const auto bytes = reinterpret_cast<const uint8_t*>(data);
-    const size_t num_blocks = (size / header_.block_size);
-    for (size_t i = 0; i < num_blocks;) {
-        const size_t blocks_to_write =
-                std::min<size_t>(batch_size_ - cached_data_.size(), num_blocks - i);
-
-        if (!ConstructCowOpCompressedBuffers(new_block_start + i, bytes + header_.block_size * i,
-                                             old_block + i, offset, type, blocks_to_write)) {
+    size_t num_blocks = (size / header_.block_size);
+    size_t total_written = 0;
+    while (total_written < num_blocks) {
+        size_t chunk = std::min(num_blocks - total_written, batch_size_);
+        if (!ConstructCowOpCompressedBuffers(new_block_start + total_written,
+                                             bytes + header_.block_size * total_written,
+                                             old_block + total_written, offset, type, chunk)) {
             return false;
         }
 
@@ -412,8 +412,7 @@
                        << ", op type: " << type;
             return false;
         }
-
-        i += blocks_to_write;
+        total_written += chunk;
     }
 
     return true;
@@ -481,7 +480,8 @@
 
     header_.sequence_data_count = num_ops;
 
-    // Ensure next_data_pos_ is updated as previously initialized + the newly added sequence buffer.
+    // Ensure next_data_pos_ is updated as previously initialized + the newly added sequence
+    // buffer.
     CHECK_EQ(next_data_pos_ + header_.sequence_data_count * sizeof(uint32_t),
              GetDataOffset(header_));
     next_data_pos_ = GetDataOffset(header_);
@@ -639,8 +639,8 @@
     //                   t1     t2     t1     t2    <- processed by these threads
     // Ordering is important here. We need to retrieve the compressed data in the same order we
     // processed it and assume that that we submit data beginning with the first thread and then
-    // round robin the consecutive data calls. We need to Fetch compressed buffers from the threads
-    // via the same ordering
+    // round robin the consecutive data calls. We need to Fetch compressed buffers from the
+    // threads via the same ordering
     for (size_t i = 0; i < compressed_vec.size(); i++) {
         compressed_buf.emplace_back(worker_buffers[i % num_threads][i / num_threads]);
     }
@@ -716,13 +716,28 @@
         return false;
     }
     if (!data.empty()) {
-        const auto ret = pwritev(fd_, data.data(), data.size(), next_data_pos_);
-        if (ret != total_data_size) {
+        int total_written = 0;
+        int i = 0;
+        while (i < data.size()) {
+            int chunk = std::min(static_cast<int>(data.size() - i), IOV_MAX);
+
+            const auto ret = pwritev(fd_, data.data() + i, chunk, next_data_pos_ + total_written);
+            if (ret < 0) {
+                PLOG(ERROR) << "write failed chunk size of: " << chunk
+                            << " at offset: " << next_data_pos_ + total_written << " " << errno;
+                return false;
+            }
+            total_written += ret;
+            i += chunk;
+        }
+        if (total_written != total_data_size) {
             PLOG(ERROR) << "write failed for data of size: " << data.size()
-                        << " at offset: " << next_data_pos_ << " " << ret;
+                        << " at offset: " << next_data_pos_ << " " << errno
+                        << ", only wrote: " << total_written;
             return false;
         }
     }
+
     header_.op_count += ops.size();
     next_data_pos_ += total_data_size;
 
diff --git a/fs_mgr/libsnapshot/libsnapshot_cow/writer_v3.h b/fs_mgr/libsnapshot/libsnapshot_cow/writer_v3.h
index 48eb67b..871ed27 100644
--- a/fs_mgr/libsnapshot/libsnapshot_cow/writer_v3.h
+++ b/fs_mgr/libsnapshot/libsnapshot_cow/writer_v3.h
@@ -28,6 +28,9 @@
 namespace snapshot {
 
 using namespace android::storage_literals;
+// This is a multiple on top of the number of data ops that can be stored in our cache at once. This
+// is added so that we can cache more non-data ops as it takes up less space.
+static constexpr uint32_t kNonDataOpBufferSize = 16;
 
 class CowWriterV3 : public CowWriterBase {
   public:
@@ -91,7 +94,7 @@
         }
         return false;
     }
-
+    size_t CachedDataSize() const;
     bool ReadBackVerification();
     bool FlushCacheOps();
     void InitWorkers();
diff --git a/fs_mgr/libsnapshot/partition_cow_creator_test.cpp b/fs_mgr/libsnapshot/partition_cow_creator_test.cpp
index cf26a16..a4a2c1a 100644
--- a/fs_mgr/libsnapshot/partition_cow_creator_test.cpp
+++ b/fs_mgr/libsnapshot/partition_cow_creator_test.cpp
@@ -39,6 +39,7 @@
 namespace android {
 namespace snapshot {
 
+// @VsrTest = 3.7.6
 class PartitionCowCreatorTest : public ::testing::Test {
   public:
     void SetUp() override {
diff --git a/fs_mgr/libsnapshot/snapshot.cpp b/fs_mgr/libsnapshot/snapshot.cpp
index e6c4de6..de91bd2 100644
--- a/fs_mgr/libsnapshot/snapshot.cpp
+++ b/fs_mgr/libsnapshot/snapshot.cpp
@@ -265,7 +265,6 @@
     auto boot_file = GetSnapshotBootIndicatorPath();
     std::string contents;
     if (!android::base::ReadFileToString(boot_file, &contents)) {
-        PLOG(WARNING) << "Cannot read " << boot_file;
         return {};
     }
     return contents;
@@ -2118,6 +2117,53 @@
     return update_status.io_uring_enabled();
 }
 
+/*
+ * Please see b/304829384 for more details.
+ *
+ * In Android S, we use dm-snapshot for mounting snapshots and snapshot-merge
+ * process. If the vendor partition continues to be on Android S, then
+ * "snapuserd" binary in first stage ramdisk will be from vendor partition.
+ * Thus, we need to maintain backward compatibility.
+ *
+ * Now, We take a two step approach to maintain the backward compatibility:
+ *
+ * 1: During OTA installation, we will continue to use "user-space" snapshots
+ * for OTA installation as both update-engine and snapuserd binary will be from system partition.
+ * However, during installation, we mark "legacy_snapuserd" in
+ * SnapshotUpdateStatus file to mark that this is a path to support backward compatibility.
+ * Thus, this function will return "false" during OTA installation.
+ *
+ * 2: Post OTA reboot, there are two key steps:
+ *    a: During first stage init, "init" and "snapuserd" could be from vendor
+ *    partition. This could be from Android S. Thus, the snapshot mount path
+ *    will be based off dm-snapshot.
+ *
+ *    b: Post selinux transition, "init" and "update-engine" will be "system"
+ *    partition. Now, since the snapshots are mounted off dm-snapshot,
+ *    update-engine interaction with "snapuserd" should work based off
+ *    dm-snapshots.
+ *
+ *    TL;DR: update-engine will use the "system" snapuserd for installing new
+ *    updates (this is safe as there is no "vendor" snapuserd running during
+ *    installation). Post reboot, update-engine will use the legacy path when
+ *    communicating with "vendor" snapuserd that was started in first-stage
+ *    init. Hence, this function checks:
+ *         i: Are we in post OTA reboot
+ *         ii: Is the Vendor from Android 12
+ *         iii: If both (i) and (ii) are true, then use the dm-snapshot based
+ *         approach.
+ *
+ */
+bool SnapshotManager::IsLegacySnapuserdPostReboot() {
+    if (is_legacy_snapuserd_.has_value() && is_legacy_snapuserd_.value() == true) {
+        auto slot = GetCurrentSlot();
+        if (slot == Slot::Target) {
+            return true;
+        }
+    }
+    return false;
+}
+
 bool SnapshotManager::UpdateUsesUserSnapshots() {
     // This and the following function is constantly
     // invoked during snapshot merge. We want to avoid
@@ -2129,7 +2175,12 @@
     // during merge phase. Hence, once we know that
     // the value is read from disk the very first time,
     // it is safe to read successive checks from memory.
+
     if (is_snapshot_userspace_.has_value()) {
+        // Check if legacy snapuserd is running post OTA reboot
+        if (IsLegacySnapuserdPostReboot()) {
+            return false;
+        }
         return is_snapshot_userspace_.value();
     }
 
@@ -2140,13 +2191,16 @@
 }
 
 bool SnapshotManager::UpdateUsesUserSnapshots(LockedFile* lock) {
-    // See UpdateUsesUserSnapshots()
-    if (is_snapshot_userspace_.has_value()) {
-        return is_snapshot_userspace_.value();
+    if (!is_snapshot_userspace_.has_value()) {
+        SnapshotUpdateStatus update_status = ReadSnapshotUpdateStatus(lock);
+        is_snapshot_userspace_ = update_status.userspace_snapshots();
+        is_legacy_snapuserd_ = update_status.legacy_snapuserd();
     }
 
-    SnapshotUpdateStatus update_status = ReadSnapshotUpdateStatus(lock);
-    is_snapshot_userspace_ = update_status.userspace_snapshots();
+    if (IsLegacySnapuserdPostReboot()) {
+        return false;
+    }
+
     return is_snapshot_userspace_.value();
 }
 
@@ -2964,6 +3018,7 @@
         status.set_merge_phase(old_status.merge_phase());
         status.set_userspace_snapshots(old_status.userspace_snapshots());
         status.set_io_uring_enabled(old_status.io_uring_enabled());
+        status.set_legacy_snapuserd(old_status.legacy_snapuserd());
     }
     return WriteSnapshotUpdateStatus(lock, status);
 }
@@ -3210,6 +3265,8 @@
     // Deduce supported features.
     bool userspace_snapshots = CanUseUserspaceSnapshots();
     bool legacy_compression = GetLegacyCompressionEnabledProperty();
+    bool is_legacy_snapuserd = IsVendorFromAndroid12();
+
     if (!vabc_disable_reason.empty()) {
         if (userspace_snapshots) {
             LOG(INFO) << "Userspace snapshots disabled: " << vabc_disable_reason;
@@ -3219,6 +3276,7 @@
         }
         userspace_snapshots = false;
         legacy_compression = false;
+        is_legacy_snapuserd = false;
     }
 
     if (legacy_compression || userspace_snapshots) {
@@ -3231,6 +3289,11 @@
         }
     }
 
+    if (!userspace_snapshots && is_legacy_snapuserd && legacy_compression) {
+        userspace_snapshots = true;
+        LOG(INFO) << "Vendor from Android 12. Enabling userspace snapshot for OTA install";
+    }
+
     const bool using_snapuserd = userspace_snapshots || legacy_compression;
     if (!using_snapuserd) {
         LOG(INFO) << "Using legacy Virtual A/B (dm-snapshot)";
@@ -3328,6 +3391,11 @@
             status.set_io_uring_enabled(true);
             LOG(INFO) << "io_uring for snapshots enabled";
         }
+
+        if (is_legacy_snapuserd) {
+            LOG(INFO) << "Setting legacy_snapuserd to true";
+            status.set_legacy_snapuserd(true);
+        }
     } else if (legacy_compression) {
         LOG(INFO) << "Virtual A/B using legacy snapuserd";
     } else {
@@ -3335,6 +3403,7 @@
     }
 
     is_snapshot_userspace_.emplace(userspace_snapshots);
+    is_legacy_snapuserd_.emplace(is_legacy_snapuserd);
 
     if (!device()->IsTestDevice() && using_snapuserd) {
         // Terminate stale daemon if any
diff --git a/fs_mgr/libsnapshot/snapshot_test.cpp b/fs_mgr/libsnapshot/snapshot_test.cpp
index e538d50..80dad17 100644
--- a/fs_mgr/libsnapshot/snapshot_test.cpp
+++ b/fs_mgr/libsnapshot/snapshot_test.cpp
@@ -56,14 +56,12 @@
 
 #if defined(LIBSNAPSHOT_TEST_VAB_LEGACY)
 #define DEFAULT_MODE "vab-legacy"
-#elif defined(LIBSNAPSHOT_TEST_VABC_LEGACY)
-#define DEFAULT_MODE "vabc-legacy"
 #else
 #define DEFAULT_MODE ""
 #endif
 
 DEFINE_string(force_mode, DEFAULT_MODE,
-              "Force testing older modes (vab-legacy, vabc-legacy) ignoring device config.");
+              "Force testing older modes (vab-legacy) ignoring device config.");
 DEFINE_string(force_iouring_disable, "",
               "Force testing mode (iouring_disabled) - disable io_uring");
 DEFINE_string(compression_method, "gz", "Default compression algorithm.");
@@ -104,6 +102,7 @@
 
 void MountMetadata();
 
+// @VsrTest = 3.7.6
 class SnapshotTest : public ::testing::Test {
   public:
     SnapshotTest() : dm_(DeviceMapper::Instance()) {}
@@ -139,17 +138,10 @@
     void SetupProperties() {
         std::unordered_map<std::string, std::string> properties;
 
-        ASSERT_TRUE(android::base::SetProperty("snapuserd.test.dm.snapshots", "0"))
-                << "Failed to disable property: virtual_ab.userspace.snapshots.enabled";
         ASSERT_TRUE(android::base::SetProperty("snapuserd.test.io_uring.force_disable", "0"))
                 << "Failed to set property: snapuserd.test.io_uring.disabled";
 
-        if (FLAGS_force_mode == "vabc-legacy") {
-            ASSERT_TRUE(android::base::SetProperty("snapuserd.test.dm.snapshots", "1"))
-                    << "Failed to disable property: virtual_ab.userspace.snapshots.enabled";
-            properties["ro.virtual_ab.compression.enabled"] = "true";
-            properties["ro.virtual_ab.userspace.snapshots.enabled"] = "false";
-        } else if (FLAGS_force_mode == "vab-legacy") {
+        if (FLAGS_force_mode == "vab-legacy") {
             properties["ro.virtual_ab.compression.enabled"] = "false";
             properties["ro.virtual_ab.userspace.snapshots.enabled"] = "false";
         }
@@ -2891,22 +2883,29 @@
     ::testing::AddGlobalTestEnvironment(new ::android::snapshot::SnapshotTestEnvironment());
     gflags::ParseCommandLineFlags(&argc, &argv, false);
 
-    android::base::SetProperty("ctl.stop", "snapuserd");
+    bool vab_legacy = false;
+    if (FLAGS_force_mode == "vab-legacy") {
+        vab_legacy = true;
+    }
 
-    std::unordered_set<std::string> modes = {"", "vab-legacy", "vabc-legacy"};
+    if (!vab_legacy) {
+        // This is necessary if the configuration we're testing doesn't match the device.
+        android::base::SetProperty("ctl.stop", "snapuserd");
+        android::snapshot::KillSnapuserd();
+    }
+
+    std::unordered_set<std::string> modes = {"", "vab-legacy"};
     if (modes.count(FLAGS_force_mode) == 0) {
         std::cerr << "Unexpected force_config argument\n";
         return 1;
     }
 
-    // This is necessary if the configuration we're testing doesn't match the device.
-    android::snapshot::KillSnapuserd();
-
     int ret = RUN_ALL_TESTS();
 
-    android::base::SetProperty("snapuserd.test.dm.snapshots", "0");
     android::base::SetProperty("snapuserd.test.io_uring.force_disable", "0");
 
-    android::snapshot::KillSnapuserd();
+    if (!vab_legacy) {
+        android::snapshot::KillSnapuserd();
+    }
     return ret;
 }
diff --git a/fs_mgr/libsnapshot/snapshotctl.cpp b/fs_mgr/libsnapshot/snapshotctl.cpp
index d1e1f07..192e1d6 100644
--- a/fs_mgr/libsnapshot/snapshotctl.cpp
+++ b/fs_mgr/libsnapshot/snapshotctl.cpp
@@ -54,6 +54,9 @@
 using namespace std::chrono_literals;
 using namespace std::string_literals;
 using namespace android::storage_literals;
+using android::base::LogdLogger;
+using android::base::StderrLogger;
+using android::base::TeeLogger;
 using android::fs_mgr::CreateLogicalPartitionParams;
 using android::fs_mgr::FindPartition;
 using android::fs_mgr::GetPartitionSize;
@@ -465,23 +468,23 @@
 #endif
 
 bool DumpCmdHandler(int /*argc*/, char** argv) {
-    android::base::InitLogging(argv, &android::base::StderrLogger);
+    android::base::InitLogging(argv, TeeLogger(LogdLogger(), &StderrLogger));
     return SnapshotManager::New()->Dump(std::cout);
 }
 
 bool MapCmdHandler(int, char** argv) {
-    android::base::InitLogging(argv, &android::base::StderrLogger);
+    android::base::InitLogging(argv, TeeLogger(LogdLogger(), &StderrLogger));
     using namespace std::chrono_literals;
     return SnapshotManager::New()->MapAllSnapshots(5000ms);
 }
 
 bool UnmapCmdHandler(int, char** argv) {
-    android::base::InitLogging(argv, &android::base::StderrLogger);
+    android::base::InitLogging(argv, TeeLogger(LogdLogger(), &StderrLogger));
     return SnapshotManager::New()->UnmapAllSnapshots();
 }
 
 bool MergeCmdHandler(int /*argc*/, char** argv) {
-    android::base::InitLogging(argv, &android::base::StderrLogger);
+    android::base::InitLogging(argv, TeeLogger(LogdLogger(), &StderrLogger));
     LOG(WARNING) << "Deprecated. Call update_engine_client --merge instead.";
     return false;
 }
diff --git a/fs_mgr/libsnapshot/snapuserd/Android.bp b/fs_mgr/libsnapshot/snapuserd/Android.bp
index bd296a3..649309d 100644
--- a/fs_mgr/libsnapshot/snapuserd/Android.bp
+++ b/fs_mgr/libsnapshot/snapuserd/Android.bp
@@ -59,9 +59,6 @@
     ],
     local_include_dirs: ["include/"],
     srcs: [
-        "dm-snapshot-merge/snapuserd.cpp",
-        "dm-snapshot-merge/snapuserd_readahead.cpp",
-        "dm-snapshot-merge/snapuserd_worker.cpp",
         "dm_user_block_server.cpp",
         "snapuserd_buffer.cpp",
         "user-space-merge/handler_manager.cpp",
@@ -109,7 +106,6 @@
         "fs_mgr_defaults",
     ],
     srcs: [
-        "dm-snapshot-merge/snapuserd_server.cpp",
         "snapuserd_daemon.cpp",
         "user-space-merge/snapuserd_server.cpp",
     ],
@@ -190,45 +186,6 @@
     symlinks: ["snapuserd"],
 }
 
-cc_test {
-    name: "snapuserd_test_legacy",
-    defaults: [
-        "fs_mgr_defaults",
-        "libsnapshot_cow_defaults",
-    ],
-    srcs: [
-        "dm-snapshot-merge/cow_snapuserd_test.cpp",
-        "dm-snapshot-merge/snapuserd.cpp",
-        "dm-snapshot-merge/snapuserd_worker.cpp",
-        "snapuserd_buffer.cpp",
-    ],
-    shared_libs: [
-        "libbase",
-        "liblog",
-    ],
-    static_libs: [
-        "libbrotli",
-        "libgtest",
-        "libsnapshot_cow",
-        "libsnapuserd_client",
-        "libcutils_sockets",
-        "libz",
-        "libdm",
-        "libext2_uuid",
-        "libext4_utils",
-        "libfs_mgr_file_wait",
-    ],
-    header_libs: [
-        "libstorage_literals_headers",
-        "libfiemap_headers",
-    ],
-    test_options: {
-        min_shipping_api_level: 30,
-    },
-    auto_gen_config: true,
-    require_root: false,
-}
-
 cc_defaults {
     name: "snapuserd_test_defaults",
     defaults: [
diff --git a/fs_mgr/libsnapshot/snapuserd/dm-snapshot-merge/cow_snapuserd_test.cpp b/fs_mgr/libsnapshot/snapuserd/dm-snapshot-merge/cow_snapuserd_test.cpp
deleted file mode 100644
index 737c480..0000000
--- a/fs_mgr/libsnapshot/snapuserd/dm-snapshot-merge/cow_snapuserd_test.cpp
+++ /dev/null
@@ -1,1238 +0,0 @@
-// Copyright (C) 2018 The Android Open Source Project
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//      http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-#include <fcntl.h>
-#include <linux/fs.h>
-#include <linux/memfd.h>
-#include <sys/ioctl.h>
-#include <sys/stat.h>
-#include <sys/syscall.h>
-#include <sys/types.h>
-#include <unistd.h>
-
-#include <chrono>
-#include <iostream>
-#include <memory>
-#include <string_view>
-
-#include <android-base/file.h>
-#include <android-base/unique_fd.h>
-#include <fs_mgr/file_wait.h>
-#include <gtest/gtest.h>
-#include <libdm/dm.h>
-#include <libdm/loop_control.h>
-#include <libsnapshot/cow_writer.h>
-#include <snapuserd/snapuserd_buffer.h>
-#include <snapuserd/snapuserd_client.h>
-#include <storage_literals/storage_literals.h>
-
-#include "snapuserd.h"
-
-namespace android {
-namespace snapshot {
-
-using namespace android::storage_literals;
-using android::base::unique_fd;
-using LoopDevice = android::dm::LoopDevice;
-using namespace std::chrono_literals;
-using namespace android::dm;
-using namespace std;
-
-static constexpr char kSnapuserdSocketTest[] = "snapuserdTest";
-
-class TempDevice {
-  public:
-    TempDevice(const std::string& name, const DmTable& table)
-        : dm_(DeviceMapper::Instance()), name_(name), valid_(false) {
-        valid_ = dm_.CreateDevice(name, table, &path_, std::chrono::seconds(5));
-    }
-    TempDevice(TempDevice&& other) noexcept
-        : dm_(other.dm_), name_(other.name_), path_(other.path_), valid_(other.valid_) {
-        other.valid_ = false;
-    }
-    ~TempDevice() {
-        if (valid_) {
-            dm_.DeleteDevice(name_);
-        }
-    }
-    bool Destroy() {
-        if (!valid_) {
-            return false;
-        }
-        valid_ = false;
-        return dm_.DeleteDevice(name_);
-    }
-    const std::string& path() const { return path_; }
-    const std::string& name() const { return name_; }
-    bool valid() const { return valid_; }
-
-    TempDevice(const TempDevice&) = delete;
-    TempDevice& operator=(const TempDevice&) = delete;
-
-    TempDevice& operator=(TempDevice&& other) noexcept {
-        name_ = other.name_;
-        valid_ = other.valid_;
-        other.valid_ = false;
-        return *this;
-    }
-
-  private:
-    DeviceMapper& dm_;
-    std::string name_;
-    std::string path_;
-    bool valid_;
-};
-
-class CowSnapuserdTest final {
-  public:
-    bool Setup();
-    bool SetupOrderedOps();
-    bool SetupOrderedOpsInverted();
-    bool SetupCopyOverlap_1();
-    bool SetupCopyOverlap_2();
-    bool Merge();
-    void ValidateMerge();
-    void ReadSnapshotDeviceAndValidate();
-    void Shutdown();
-    void MergeInterrupt();
-    void MergeInterruptFixed(int duration);
-    void MergeInterruptRandomly(int max_duration);
-    void ReadDmUserBlockWithoutDaemon();
-    void ReadLastBlock();
-
-    std::string snapshot_dev() const { return snapshot_dev_->path(); }
-
-    static const uint64_t kSectorSize = 512;
-
-  private:
-    void SetupImpl();
-
-    void MergeImpl();
-    void SimulateDaemonRestart();
-    void StartMerge();
-
-    std::unique_ptr<ICowWriter> CreateCowDeviceInternal();
-    void CreateCowDevice();
-    void CreateCowDeviceOrderedOps();
-    void CreateCowDeviceOrderedOpsInverted();
-    void CreateCowDeviceWithCopyOverlap_1();
-    void CreateCowDeviceWithCopyOverlap_2();
-    bool SetupDaemon();
-    void CreateBaseDevice();
-    void InitCowDevice();
-    void SetDeviceControlName();
-    void InitDaemon();
-    void CreateDmUserDevice();
-    void StartSnapuserdDaemon();
-    void CreateSnapshotDevice();
-
-    unique_ptr<LoopDevice> base_loop_;
-    unique_ptr<TempDevice> dmuser_dev_;
-    unique_ptr<TempDevice> snapshot_dev_;
-
-    std::string system_device_ctrl_name_;
-    std::string system_device_name_;
-
-    unique_fd base_fd_;
-    std::unique_ptr<TemporaryFile> cow_system_;
-    std::unique_ptr<SnapuserdClient> client_;
-    std::unique_ptr<uint8_t[]> orig_buffer_;
-    std::unique_ptr<uint8_t[]> merged_buffer_;
-    bool setup_ok_ = false;
-    bool merge_ok_ = false;
-    size_t size_ = 50_MiB;
-    int cow_num_sectors_;
-    int total_base_size_;
-};
-
-class CowSnapuserdMetadataTest final {
-  public:
-    void Setup();
-    void SetupPartialArea();
-    void ValidateMetadata();
-    void ValidatePartialFilledArea();
-
-  private:
-    void InitMetadata();
-    std::unique_ptr<ICowWriter> CreateCowDeviceInternal();
-    void CreateCowDevice();
-    void CreateCowPartialFilledArea();
-
-    std::unique_ptr<Snapuserd> snapuserd_;
-    std::unique_ptr<TemporaryFile> cow_system_;
-    size_t size_ = 1_MiB;
-};
-
-static unique_fd CreateTempFile(const std::string& name, size_t size) {
-    unique_fd fd(syscall(__NR_memfd_create, name.c_str(), MFD_ALLOW_SEALING));
-    if (fd < 0) {
-        return {};
-    }
-    if (size) {
-        if (ftruncate(fd, size) < 0) {
-            perror("ftruncate");
-            return {};
-        }
-        if (fcntl(fd, F_ADD_SEALS, F_SEAL_GROW | F_SEAL_SHRINK) < 0) {
-            perror("fcntl");
-            return {};
-        }
-    }
-    return fd;
-}
-
-void CowSnapuserdTest::Shutdown() {
-    ASSERT_TRUE(snapshot_dev_->Destroy());
-    ASSERT_TRUE(dmuser_dev_->Destroy());
-
-    auto misc_device = "/dev/dm-user/" + system_device_ctrl_name_;
-    ASSERT_TRUE(client_->WaitForDeviceDelete(system_device_ctrl_name_));
-    ASSERT_TRUE(android::fs_mgr::WaitForFileDeleted(misc_device, 10s));
-    ASSERT_TRUE(client_->DetachSnapuserd());
-}
-
-bool CowSnapuserdTest::Setup() {
-    SetupImpl();
-    return setup_ok_;
-}
-
-bool CowSnapuserdTest::SetupOrderedOps() {
-    CreateBaseDevice();
-    CreateCowDeviceOrderedOps();
-    return SetupDaemon();
-}
-
-bool CowSnapuserdTest::SetupOrderedOpsInverted() {
-    CreateBaseDevice();
-    CreateCowDeviceOrderedOpsInverted();
-    return SetupDaemon();
-}
-
-bool CowSnapuserdTest::SetupCopyOverlap_1() {
-    CreateBaseDevice();
-    CreateCowDeviceWithCopyOverlap_1();
-    return SetupDaemon();
-}
-
-bool CowSnapuserdTest::SetupCopyOverlap_2() {
-    CreateBaseDevice();
-    CreateCowDeviceWithCopyOverlap_2();
-    return SetupDaemon();
-}
-
-bool CowSnapuserdTest::SetupDaemon() {
-    SetDeviceControlName();
-
-    StartSnapuserdDaemon();
-    InitCowDevice();
-
-    CreateDmUserDevice();
-    InitDaemon();
-
-    CreateSnapshotDevice();
-    setup_ok_ = true;
-
-    return setup_ok_;
-}
-
-void CowSnapuserdTest::StartSnapuserdDaemon() {
-    pid_t pid = fork();
-    ASSERT_GE(pid, 0);
-    if (pid == 0) {
-        std::string arg0 = "/system/bin/snapuserd";
-        std::string arg1 = "-socket="s + kSnapuserdSocketTest;
-        char* const argv[] = {arg0.data(), arg1.data(), nullptr};
-        ASSERT_GE(execv(arg0.c_str(), argv), 0);
-    } else {
-        client_ = SnapuserdClient::Connect(kSnapuserdSocketTest, 10s);
-        ASSERT_NE(client_, nullptr);
-    }
-}
-
-std::unique_ptr<ICowWriter> CowSnapuserdTest::CreateCowDeviceInternal() {
-    std::string path = android::base::GetExecutableDirectory();
-    cow_system_ = std::make_unique<TemporaryFile>(path);
-
-    CowOptions options;
-    options.compression = "gz";
-
-    unique_fd fd(cow_system_->fd);
-    cow_system_->fd = -1;
-
-    return CreateCowWriter(kDefaultCowVersion, options, std::move(fd));
-}
-
-void CowSnapuserdTest::ReadLastBlock() {
-    unique_fd rnd_fd;
-    total_base_size_ = BLOCK_SZ * 2;
-
-    base_fd_ = CreateTempFile("base_device", total_base_size_);
-    ASSERT_GE(base_fd_, 0);
-
-    rnd_fd.reset(open("/dev/random", O_RDONLY));
-    ASSERT_TRUE(rnd_fd > 0);
-
-    std::unique_ptr<uint8_t[]> random_buffer = std::make_unique<uint8_t[]>(BLOCK_SZ);
-
-    for (size_t j = 0; j < ((total_base_size_) / BLOCK_SZ); j++) {
-        ASSERT_EQ(ReadFullyAtOffset(rnd_fd, (char*)random_buffer.get(), BLOCK_SZ, 0), true);
-        ASSERT_EQ(android::base::WriteFully(base_fd_, random_buffer.get(), BLOCK_SZ), true);
-    }
-
-    ASSERT_EQ(lseek(base_fd_, 0, SEEK_SET), 0);
-
-    base_loop_ = std::make_unique<LoopDevice>(base_fd_, 10s);
-    ASSERT_TRUE(base_loop_->valid());
-
-    std::unique_ptr<uint8_t[]> random_buffer_1_ = std::make_unique<uint8_t[]>(total_base_size_);
-    loff_t offset = 0;
-
-    // Fill random data
-    for (size_t j = 0; j < (total_base_size_ / BLOCK_SZ); j++) {
-        ASSERT_EQ(ReadFullyAtOffset(rnd_fd, (char*)random_buffer_1_.get() + offset, BLOCK_SZ, 0),
-                  true);
-
-        offset += BLOCK_SZ;
-    }
-
-    auto writer = CreateCowDeviceInternal();
-    ASSERT_NE(writer, nullptr);
-
-    ASSERT_TRUE(writer->AddRawBlocks(0, random_buffer_1_.get(), BLOCK_SZ));
-    ASSERT_TRUE(writer->AddRawBlocks(1, (char*)random_buffer_1_.get() + BLOCK_SZ, BLOCK_SZ));
-
-    ASSERT_TRUE(writer->Finalize());
-
-    SetDeviceControlName();
-
-    StartSnapuserdDaemon();
-    InitCowDevice();
-
-    CreateDmUserDevice();
-    InitDaemon();
-
-    CreateSnapshotDevice();
-
-    unique_fd snapshot_fd(open(snapshot_dev_->path().c_str(), O_RDONLY));
-    ASSERT_TRUE(snapshot_fd > 0);
-
-    std::unique_ptr<uint8_t[]> snapuserd_buffer = std::make_unique<uint8_t[]>(BLOCK_SZ);
-
-    offset = 7680;
-    ASSERT_EQ(ReadFullyAtOffset(snapshot_fd, snapuserd_buffer.get(), 512, offset), true);
-    ASSERT_EQ(memcmp(snapuserd_buffer.get(), (char*)random_buffer_1_.get() + offset, 512), 0);
-}
-
-void CowSnapuserdTest::CreateBaseDevice() {
-    unique_fd rnd_fd;
-
-    total_base_size_ = (size_ * 5);
-    base_fd_ = CreateTempFile("base_device", total_base_size_);
-    ASSERT_GE(base_fd_, 0);
-
-    rnd_fd.reset(open("/dev/random", O_RDONLY));
-    ASSERT_TRUE(rnd_fd > 0);
-
-    std::unique_ptr<uint8_t[]> random_buffer = std::make_unique<uint8_t[]>(1_MiB);
-
-    for (size_t j = 0; j < ((total_base_size_) / 1_MiB); j++) {
-        ASSERT_EQ(ReadFullyAtOffset(rnd_fd, (char*)random_buffer.get(), 1_MiB, 0), true);
-        ASSERT_EQ(android::base::WriteFully(base_fd_, random_buffer.get(), 1_MiB), true);
-    }
-
-    ASSERT_EQ(lseek(base_fd_, 0, SEEK_SET), 0);
-
-    base_loop_ = std::make_unique<LoopDevice>(base_fd_, 10s);
-    ASSERT_TRUE(base_loop_->valid());
-}
-
-void CowSnapuserdTest::ReadSnapshotDeviceAndValidate() {
-    unique_fd snapshot_fd(open(snapshot_dev_->path().c_str(), O_RDONLY));
-    ASSERT_TRUE(snapshot_fd > 0);
-
-    std::unique_ptr<uint8_t[]> snapuserd_buffer = std::make_unique<uint8_t[]>(size_);
-
-    // COPY
-    loff_t offset = 0;
-    ASSERT_EQ(ReadFullyAtOffset(snapshot_fd, snapuserd_buffer.get(), size_, offset), true);
-    ASSERT_EQ(memcmp(snapuserd_buffer.get(), orig_buffer_.get(), size_), 0);
-
-    // REPLACE
-    offset += size_;
-    ASSERT_EQ(ReadFullyAtOffset(snapshot_fd, snapuserd_buffer.get(), size_, offset), true);
-    ASSERT_EQ(memcmp(snapuserd_buffer.get(), (char*)orig_buffer_.get() + size_, size_), 0);
-
-    // ZERO
-    offset += size_;
-    ASSERT_EQ(ReadFullyAtOffset(snapshot_fd, snapuserd_buffer.get(), size_, offset), true);
-    ASSERT_EQ(memcmp(snapuserd_buffer.get(), (char*)orig_buffer_.get() + (size_ * 2), size_), 0);
-
-    // REPLACE
-    offset += size_;
-    ASSERT_EQ(ReadFullyAtOffset(snapshot_fd, snapuserd_buffer.get(), size_, offset), true);
-    ASSERT_EQ(memcmp(snapuserd_buffer.get(), (char*)orig_buffer_.get() + (size_ * 3), size_), 0);
-
-    // XOR
-    offset += size_;
-    ASSERT_EQ(ReadFullyAtOffset(snapshot_fd, snapuserd_buffer.get(), size_, offset), true);
-    ASSERT_EQ(memcmp(snapuserd_buffer.get(), (char*)orig_buffer_.get() + (size_ * 4), size_), 0);
-}
-
-void CowSnapuserdTest::CreateCowDeviceWithCopyOverlap_2() {
-    auto writer = CreateCowDeviceInternal();
-    ASSERT_NE(writer, nullptr);
-
-    size_t num_blocks = size_ / writer->GetBlockSize();
-    size_t x = num_blocks;
-    size_t blk_src_copy = 0;
-
-    // Create overlapping copy operations
-    while (1) {
-        ASSERT_TRUE(writer->AddCopy(blk_src_copy, blk_src_copy + 1));
-        x -= 1;
-        if (x == 1) {
-            break;
-        }
-        blk_src_copy += 1;
-    }
-
-    // Flush operations
-    ASSERT_TRUE(writer->Finalize());
-
-    // Construct the buffer required for validation
-    orig_buffer_ = std::make_unique<uint8_t[]>(total_base_size_);
-
-    // Read the entire base device
-    ASSERT_EQ(android::base::ReadFullyAtOffset(base_fd_, orig_buffer_.get(), total_base_size_, 0),
-              true);
-
-    // Merged operations required for validation
-    int block_size = 4096;
-    x = num_blocks;
-    loff_t src_offset = block_size;
-    loff_t dest_offset = 0;
-
-    while (1) {
-        memmove((char*)orig_buffer_.get() + dest_offset, (char*)orig_buffer_.get() + src_offset,
-                block_size);
-        x -= 1;
-        if (x == 1) {
-            break;
-        }
-        src_offset += block_size;
-        dest_offset += block_size;
-    }
-}
-
-void CowSnapuserdTest::CreateCowDeviceWithCopyOverlap_1() {
-    auto writer = CreateCowDeviceInternal();
-    ASSERT_NE(writer, nullptr);
-
-    size_t num_blocks = size_ / writer->GetBlockSize();
-    size_t x = num_blocks;
-    size_t blk_src_copy = num_blocks - 1;
-
-    // Create overlapping copy operations
-    while (1) {
-        ASSERT_TRUE(writer->AddCopy(blk_src_copy + 1, blk_src_copy));
-        x -= 1;
-        if (x == 0) {
-            ASSERT_EQ(blk_src_copy, 0);
-            break;
-        }
-        blk_src_copy -= 1;
-    }
-
-    // Flush operations
-    ASSERT_TRUE(writer->Finalize());
-
-    // Construct the buffer required for validation
-    orig_buffer_ = std::make_unique<uint8_t[]>(total_base_size_);
-
-    // Read the entire base device
-    ASSERT_EQ(android::base::ReadFullyAtOffset(base_fd_, orig_buffer_.get(), total_base_size_, 0),
-              true);
-
-    // Merged operations
-    ASSERT_EQ(android::base::ReadFullyAtOffset(base_fd_, orig_buffer_.get(), writer->GetBlockSize(),
-                                               0),
-              true);
-    ASSERT_EQ(android::base::ReadFullyAtOffset(
-                      base_fd_, (char*)orig_buffer_.get() + writer->GetBlockSize(), size_, 0),
-              true);
-}
-
-void CowSnapuserdTest::CreateCowDeviceOrderedOpsInverted() {
-    unique_fd rnd_fd;
-    loff_t offset = 0;
-
-    auto writer = CreateCowDeviceInternal();
-    ASSERT_NE(writer, nullptr);
-
-    rnd_fd.reset(open("/dev/random", O_RDONLY));
-    ASSERT_TRUE(rnd_fd > 0);
-
-    std::unique_ptr<uint8_t[]> random_buffer_1_ = std::make_unique<uint8_t[]>(size_);
-
-    // Fill random data
-    for (size_t j = 0; j < (size_ / 1_MiB); j++) {
-        ASSERT_EQ(ReadFullyAtOffset(rnd_fd, (char*)random_buffer_1_.get() + offset, 1_MiB, 0),
-                  true);
-
-        offset += 1_MiB;
-    }
-
-    size_t num_blocks = size_ / writer->GetBlockSize();
-    size_t blk_end_copy = num_blocks * 3;
-    size_t source_blk = num_blocks - 1;
-    size_t blk_src_copy = blk_end_copy - 1;
-    uint16_t xor_offset = 5;
-
-    size_t x = num_blocks;
-    while (1) {
-        ASSERT_TRUE(writer->AddCopy(source_blk, blk_src_copy));
-        x -= 1;
-        if (x == 0) {
-            break;
-        }
-        source_blk -= 1;
-        blk_src_copy -= 1;
-    }
-
-    for (size_t i = num_blocks; i > 0; i--) {
-        ASSERT_TRUE(writer->AddXorBlocks(
-                num_blocks + i - 1, &random_buffer_1_.get()[writer->GetBlockSize() * (i - 1)],
-                writer->GetBlockSize(), 2 * num_blocks + i - 1, xor_offset));
-    }
-    // Flush operations
-    ASSERT_TRUE(writer->Finalize());
-    // Construct the buffer required for validation
-    orig_buffer_ = std::make_unique<uint8_t[]>(total_base_size_);
-    // Read the entire base device
-    ASSERT_EQ(android::base::ReadFullyAtOffset(base_fd_, orig_buffer_.get(), total_base_size_, 0),
-              true);
-    // Merged Buffer
-    memmove(orig_buffer_.get(), (char*)orig_buffer_.get() + 2 * size_, size_);
-    memmove(orig_buffer_.get() + size_, (char*)orig_buffer_.get() + 2 * size_ + xor_offset, size_);
-    for (int i = 0; i < size_; i++) {
-        orig_buffer_.get()[size_ + i] ^= random_buffer_1_.get()[i];
-    }
-}
-
-void CowSnapuserdTest::CreateCowDeviceOrderedOps() {
-    unique_fd rnd_fd;
-    loff_t offset = 0;
-
-    auto writer = CreateCowDeviceInternal();
-    ASSERT_NE(writer, nullptr);
-
-    rnd_fd.reset(open("/dev/random", O_RDONLY));
-    ASSERT_TRUE(rnd_fd > 0);
-
-    std::unique_ptr<uint8_t[]> random_buffer_1_ = std::make_unique<uint8_t[]>(size_);
-
-    // Fill random data
-    for (size_t j = 0; j < (size_ / 1_MiB); j++) {
-        ASSERT_EQ(ReadFullyAtOffset(rnd_fd, (char*)random_buffer_1_.get() + offset, 1_MiB, 0),
-                  true);
-
-        offset += 1_MiB;
-    }
-    memset(random_buffer_1_.get(), 0, size_);
-
-    size_t num_blocks = size_ / writer->GetBlockSize();
-    size_t x = num_blocks;
-    size_t source_blk = 0;
-    size_t blk_src_copy = 2 * num_blocks;
-    uint16_t xor_offset = 5;
-
-    while (1) {
-        ASSERT_TRUE(writer->AddCopy(source_blk, blk_src_copy));
-
-        x -= 1;
-        if (x == 0) {
-            break;
-        }
-        source_blk += 1;
-        blk_src_copy += 1;
-    }
-
-    ASSERT_TRUE(writer->AddXorBlocks(num_blocks, random_buffer_1_.get(), size_, 2 * num_blocks,
-                                     xor_offset));
-    // Flush operations
-    ASSERT_TRUE(writer->Finalize());
-    // Construct the buffer required for validation
-    orig_buffer_ = std::make_unique<uint8_t[]>(total_base_size_);
-    // Read the entire base device
-    ASSERT_EQ(android::base::ReadFullyAtOffset(base_fd_, orig_buffer_.get(), total_base_size_, 0),
-              true);
-    // Merged Buffer
-    memmove(orig_buffer_.get(), (char*)orig_buffer_.get() + 2 * size_, size_);
-    memmove(orig_buffer_.get() + size_, (char*)orig_buffer_.get() + 2 * size_ + xor_offset, size_);
-    for (int i = 0; i < size_; i++) {
-        orig_buffer_.get()[size_ + i] ^= random_buffer_1_.get()[i];
-    }
-}
-
-void CowSnapuserdTest::CreateCowDevice() {
-    unique_fd rnd_fd;
-    loff_t offset = 0;
-
-    auto writer = CreateCowDeviceInternal();
-    ASSERT_NE(writer, nullptr);
-
-    rnd_fd.reset(open("/dev/random", O_RDONLY));
-    ASSERT_TRUE(rnd_fd > 0);
-
-    std::unique_ptr<uint8_t[]> random_buffer_1_ = std::make_unique<uint8_t[]>(size_);
-
-    // Fill random data
-    for (size_t j = 0; j < (size_ / 1_MiB); j++) {
-        ASSERT_EQ(ReadFullyAtOffset(rnd_fd, (char*)random_buffer_1_.get() + offset, 1_MiB, 0),
-                  true);
-
-        offset += 1_MiB;
-    }
-
-    size_t num_blocks = size_ / writer->GetBlockSize();
-    size_t blk_end_copy = num_blocks * 2;
-    size_t source_blk = num_blocks - 1;
-    size_t blk_src_copy = blk_end_copy - 1;
-
-    uint32_t sequence[num_blocks * 2];
-    // Sequence for Copy ops
-    for (int i = 0; i < num_blocks; i++) {
-        sequence[i] = num_blocks - 1 - i;
-    }
-    // Sequence for Xor ops
-    for (int i = 0; i < num_blocks; i++) {
-        sequence[num_blocks + i] = 5 * num_blocks - 1 - i;
-    }
-    ASSERT_TRUE(writer->AddSequenceData(2 * num_blocks, sequence));
-
-    size_t x = num_blocks;
-    while (1) {
-        ASSERT_TRUE(writer->AddCopy(source_blk, blk_src_copy));
-        x -= 1;
-        if (x == 0) {
-            break;
-        }
-        source_blk -= 1;
-        blk_src_copy -= 1;
-    }
-
-    source_blk = num_blocks;
-    blk_src_copy = blk_end_copy;
-
-    ASSERT_TRUE(writer->AddRawBlocks(source_blk, random_buffer_1_.get(), size_));
-
-    size_t blk_zero_copy_start = source_blk + num_blocks;
-    size_t blk_zero_copy_end = blk_zero_copy_start + num_blocks;
-
-    ASSERT_TRUE(writer->AddZeroBlocks(blk_zero_copy_start, num_blocks));
-
-    size_t blk_random2_replace_start = blk_zero_copy_end;
-
-    ASSERT_TRUE(writer->AddRawBlocks(blk_random2_replace_start, random_buffer_1_.get(), size_));
-
-    size_t blk_xor_start = blk_random2_replace_start + num_blocks;
-    size_t xor_offset = BLOCK_SZ / 2;
-    ASSERT_TRUE(writer->AddXorBlocks(blk_xor_start, random_buffer_1_.get(), size_, num_blocks,
-                                     xor_offset));
-
-    // Flush operations
-    ASSERT_TRUE(writer->Finalize());
-    // Construct the buffer required for validation
-    orig_buffer_ = std::make_unique<uint8_t[]>(total_base_size_);
-    std::string zero_buffer(size_, 0);
-    ASSERT_EQ(android::base::ReadFullyAtOffset(base_fd_, orig_buffer_.get(), size_, size_), true);
-    memcpy((char*)orig_buffer_.get() + size_, random_buffer_1_.get(), size_);
-    memcpy((char*)orig_buffer_.get() + (size_ * 2), (void*)zero_buffer.c_str(), size_);
-    memcpy((char*)orig_buffer_.get() + (size_ * 3), random_buffer_1_.get(), size_);
-    ASSERT_EQ(android::base::ReadFullyAtOffset(base_fd_, &orig_buffer_.get()[size_ * 4], size_,
-                                               size_ + xor_offset),
-              true);
-    for (int i = 0; i < size_; i++) {
-        orig_buffer_.get()[(size_ * 4) + i] =
-                (uint8_t)(orig_buffer_.get()[(size_ * 4) + i] ^ random_buffer_1_.get()[i]);
-    }
-}
-
-void CowSnapuserdTest::InitCowDevice() {
-    cow_num_sectors_ = client_->InitDmUserCow(system_device_ctrl_name_, cow_system_->path,
-                                              base_loop_->device());
-    ASSERT_NE(cow_num_sectors_, 0);
-}
-
-void CowSnapuserdTest::SetDeviceControlName() {
-    system_device_name_.clear();
-    system_device_ctrl_name_.clear();
-
-    std::string str(cow_system_->path);
-    std::size_t found = str.find_last_of("/\\");
-    ASSERT_NE(found, std::string::npos);
-    system_device_name_ = str.substr(found + 1);
-
-    system_device_ctrl_name_ = system_device_name_ + "-ctrl";
-}
-
-void CowSnapuserdTest::CreateDmUserDevice() {
-    DmTable dmuser_table;
-    ASSERT_TRUE(dmuser_table.AddTarget(
-            std::make_unique<DmTargetUser>(0, cow_num_sectors_, system_device_ctrl_name_)));
-    ASSERT_TRUE(dmuser_table.valid());
-
-    dmuser_dev_ = std::make_unique<TempDevice>(system_device_name_, dmuser_table);
-    ASSERT_TRUE(dmuser_dev_->valid());
-    ASSERT_FALSE(dmuser_dev_->path().empty());
-
-    auto misc_device = "/dev/dm-user/" + system_device_ctrl_name_;
-    ASSERT_TRUE(android::fs_mgr::WaitForFile(misc_device, 10s));
-}
-
-void CowSnapuserdTest::ReadDmUserBlockWithoutDaemon() {
-    DmTable dmuser_table;
-    std::string dm_user_name = "dm-test-device";
-    unique_fd fd;
-
-    // Create a dm-user block device
-    ASSERT_TRUE(dmuser_table.AddTarget(std::make_unique<DmTargetUser>(0, 123456, dm_user_name)));
-    ASSERT_TRUE(dmuser_table.valid());
-
-    dmuser_dev_ = std::make_unique<TempDevice>(dm_user_name, dmuser_table);
-    ASSERT_TRUE(dmuser_dev_->valid());
-    ASSERT_FALSE(dmuser_dev_->path().empty());
-
-    fd.reset(open(dmuser_dev_->path().c_str(), O_RDONLY));
-    ASSERT_GE(fd, 0);
-
-    std::unique_ptr<uint8_t[]> buffer = std::make_unique<uint8_t[]>(1_MiB);
-
-    loff_t offset = 0;
-    // Every IO should fail as there is no daemon to process the IO
-    for (size_t j = 0; j < 10; j++) {
-        ASSERT_EQ(ReadFullyAtOffset(fd, (char*)buffer.get() + offset, BLOCK_SZ, offset), false);
-
-        offset += BLOCK_SZ;
-    }
-
-    fd = {};
-    ASSERT_TRUE(dmuser_dev_->Destroy());
-}
-
-void CowSnapuserdTest::InitDaemon() {
-    bool ok = client_->AttachDmUser(system_device_ctrl_name_);
-    ASSERT_TRUE(ok);
-}
-
-void CowSnapuserdTest::CreateSnapshotDevice() {
-    DmTable snap_table;
-    ASSERT_TRUE(snap_table.AddTarget(std::make_unique<DmTargetSnapshot>(
-            0, total_base_size_ / kSectorSize, base_loop_->device(), dmuser_dev_->path(),
-            SnapshotStorageMode::Persistent, 8)));
-    ASSERT_TRUE(snap_table.valid());
-
-    snap_table.set_readonly(true);
-
-    snapshot_dev_ = std::make_unique<TempDevice>("cowsnapuserd-test-dm-snapshot", snap_table);
-    ASSERT_TRUE(snapshot_dev_->valid());
-    ASSERT_FALSE(snapshot_dev_->path().empty());
-}
-
-void CowSnapuserdTest::SetupImpl() {
-    CreateBaseDevice();
-    CreateCowDevice();
-
-    SetDeviceControlName();
-
-    StartSnapuserdDaemon();
-    InitCowDevice();
-
-    CreateDmUserDevice();
-    InitDaemon();
-
-    CreateSnapshotDevice();
-    setup_ok_ = true;
-}
-
-bool CowSnapuserdTest::Merge() {
-    MergeImpl();
-    return merge_ok_;
-}
-
-void CowSnapuserdTest::StartMerge() {
-    DmTable merge_table;
-    ASSERT_TRUE(merge_table.AddTarget(std::make_unique<DmTargetSnapshot>(
-            0, total_base_size_ / kSectorSize, base_loop_->device(), dmuser_dev_->path(),
-            SnapshotStorageMode::Merge, 8)));
-    ASSERT_TRUE(merge_table.valid());
-    ASSERT_EQ(total_base_size_ / kSectorSize, merge_table.num_sectors());
-
-    DeviceMapper& dm = DeviceMapper::Instance();
-    ASSERT_TRUE(dm.LoadTableAndActivate("cowsnapuserd-test-dm-snapshot", merge_table));
-}
-
-void CowSnapuserdTest::MergeImpl() {
-    StartMerge();
-    DeviceMapper& dm = DeviceMapper::Instance();
-
-    while (true) {
-        vector<DeviceMapper::TargetInfo> status;
-        ASSERT_TRUE(dm.GetTableStatus("cowsnapuserd-test-dm-snapshot", &status));
-        ASSERT_EQ(status.size(), 1);
-        ASSERT_EQ(strncmp(status[0].spec.target_type, "snapshot-merge", strlen("snapshot-merge")),
-                  0);
-
-        DmTargetSnapshot::Status merge_status;
-        ASSERT_TRUE(DmTargetSnapshot::ParseStatusText(status[0].data, &merge_status));
-        ASSERT_TRUE(merge_status.error.empty());
-        if (merge_status.sectors_allocated == merge_status.metadata_sectors) {
-            break;
-        }
-
-        std::this_thread::sleep_for(250ms);
-    }
-
-    merge_ok_ = true;
-}
-
-void CowSnapuserdTest::ValidateMerge() {
-    merged_buffer_ = std::make_unique<uint8_t[]>(total_base_size_);
-    ASSERT_EQ(android::base::ReadFullyAtOffset(base_fd_, merged_buffer_.get(), total_base_size_, 0),
-              true);
-    ASSERT_EQ(memcmp(merged_buffer_.get(), orig_buffer_.get(), total_base_size_), 0);
-}
-
-void CowSnapuserdTest::SimulateDaemonRestart() {
-    Shutdown();
-    std::this_thread::sleep_for(500ms);
-    SetDeviceControlName();
-    StartSnapuserdDaemon();
-    InitCowDevice();
-    CreateDmUserDevice();
-    InitDaemon();
-    CreateSnapshotDevice();
-}
-
-void CowSnapuserdTest::MergeInterruptRandomly(int max_duration) {
-    std::srand(std::time(nullptr));
-    StartMerge();
-
-    for (int i = 0; i < 20; i++) {
-        int duration = std::rand() % max_duration;
-        std::this_thread::sleep_for(std::chrono::milliseconds(duration));
-        SimulateDaemonRestart();
-        StartMerge();
-    }
-
-    SimulateDaemonRestart();
-    ASSERT_TRUE(Merge());
-}
-
-void CowSnapuserdTest::MergeInterruptFixed(int duration) {
-    StartMerge();
-
-    for (int i = 0; i < 25; i++) {
-        std::this_thread::sleep_for(std::chrono::milliseconds(duration));
-        SimulateDaemonRestart();
-        StartMerge();
-    }
-
-    SimulateDaemonRestart();
-    ASSERT_TRUE(Merge());
-}
-
-void CowSnapuserdTest::MergeInterrupt() {
-    // Interrupt merge at various intervals
-    StartMerge();
-    std::this_thread::sleep_for(250ms);
-    SimulateDaemonRestart();
-
-    StartMerge();
-    std::this_thread::sleep_for(250ms);
-    SimulateDaemonRestart();
-
-    StartMerge();
-    std::this_thread::sleep_for(150ms);
-    SimulateDaemonRestart();
-
-    StartMerge();
-    std::this_thread::sleep_for(100ms);
-    SimulateDaemonRestart();
-
-    StartMerge();
-    std::this_thread::sleep_for(800ms);
-    SimulateDaemonRestart();
-
-    StartMerge();
-    std::this_thread::sleep_for(600ms);
-    SimulateDaemonRestart();
-
-    ASSERT_TRUE(Merge());
-}
-
-std::unique_ptr<ICowWriter> CowSnapuserdMetadataTest::CreateCowDeviceInternal() {
-    std::string path = android::base::GetExecutableDirectory();
-    cow_system_ = std::make_unique<TemporaryFile>(path);
-
-    CowOptions options;
-    options.compression = "gz";
-
-    unique_fd fd(cow_system_->fd);
-    cow_system_->fd = -1;
-
-    return CreateCowWriter(kDefaultCowVersion, options, std::move(fd));
-}
-
-void CowSnapuserdMetadataTest::CreateCowPartialFilledArea() {
-    auto writer = CreateCowDeviceInternal();
-    ASSERT_NE(writer, nullptr);
-
-    // Area 0 is completely filled with 256 exceptions
-    for (int i = 0; i < 256; i++) {
-        ASSERT_TRUE(writer->AddCopy(i, 256 + i));
-    }
-
-    // Area 1 is partially filled with 2 copy ops and 10 zero ops
-    ASSERT_TRUE(writer->AddCopy(500, 1000));
-    ASSERT_TRUE(writer->AddCopy(501, 1001));
-
-    ASSERT_TRUE(writer->AddZeroBlocks(300, 10));
-
-    // Flush operations
-    ASSERT_TRUE(writer->Finalize());
-}
-
-void CowSnapuserdMetadataTest::ValidatePartialFilledArea() {
-    int area_sz = snapuserd_->GetMetadataAreaSize();
-
-    ASSERT_EQ(area_sz, 2);
-
-    // Verify the partially filled area
-    void* buffer = snapuserd_->GetExceptionBuffer(1);
-    loff_t offset = 0;
-    struct disk_exception* de;
-    for (int i = 11; i >= 0; i--) {
-        de = reinterpret_cast<struct disk_exception*>((char*)buffer + offset);
-        ASSERT_EQ(de->old_chunk, i);
-        offset += sizeof(struct disk_exception);
-    }
-
-    de = reinterpret_cast<struct disk_exception*>((char*)buffer + offset);
-    ASSERT_EQ(de->old_chunk, 0);
-    ASSERT_EQ(de->new_chunk, 0);
-}
-
-void CowSnapuserdMetadataTest::SetupPartialArea() {
-    CreateCowPartialFilledArea();
-    InitMetadata();
-}
-
-void CowSnapuserdMetadataTest::CreateCowDevice() {
-    unique_fd rnd_fd;
-    loff_t offset = 0;
-
-    auto writer = CreateCowDeviceInternal();
-    ASSERT_NE(writer, nullptr);
-
-    rnd_fd.reset(open("/dev/random", O_RDONLY));
-    ASSERT_TRUE(rnd_fd > 0);
-
-    std::unique_ptr<uint8_t[]> random_buffer_1_ = std::make_unique<uint8_t[]>(size_);
-
-    // Fill random data
-    for (size_t j = 0; j < (size_ / 1_MiB); j++) {
-        ASSERT_EQ(ReadFullyAtOffset(rnd_fd, (char*)random_buffer_1_.get() + offset, 1_MiB, 0),
-                  true);
-
-        offset += 1_MiB;
-    }
-
-    size_t num_blocks = size_ / writer->GetBlockSize();
-
-    // Overlapping region. This has to be split
-    // into two batch operations
-    ASSERT_TRUE(writer->AddCopy(23, 20));
-    ASSERT_TRUE(writer->AddCopy(22, 19));
-    ASSERT_TRUE(writer->AddCopy(21, 18));
-    ASSERT_TRUE(writer->AddCopy(20, 17));
-    ASSERT_TRUE(writer->AddCopy(19, 16));
-    ASSERT_TRUE(writer->AddCopy(18, 15));
-
-    // Contiguous region but blocks in ascending order
-    // Daemon has to ensure that these blocks are merged
-    // in a batch
-    ASSERT_TRUE(writer->AddCopy(50, 75));
-    ASSERT_TRUE(writer->AddCopy(51, 76));
-    ASSERT_TRUE(writer->AddCopy(52, 77));
-    ASSERT_TRUE(writer->AddCopy(53, 78));
-
-    // Dis-contiguous region
-    ASSERT_TRUE(writer->AddCopy(110, 130));
-    ASSERT_TRUE(writer->AddCopy(105, 125));
-    ASSERT_TRUE(writer->AddCopy(100, 120));
-
-    // Overlap
-    ASSERT_TRUE(writer->AddCopy(25, 30));
-    ASSERT_TRUE(writer->AddCopy(30, 31));
-
-    size_t source_blk = num_blocks;
-
-    ASSERT_TRUE(writer->AddRawBlocks(source_blk, random_buffer_1_.get(), size_));
-
-    size_t blk_zero_copy_start = source_blk + num_blocks;
-
-    ASSERT_TRUE(writer->AddZeroBlocks(blk_zero_copy_start, num_blocks));
-
-    // Flush operations
-    ASSERT_TRUE(writer->Finalize());
-}
-
-void CowSnapuserdMetadataTest::InitMetadata() {
-    snapuserd_ = std::make_unique<Snapuserd>("", cow_system_->path, "");
-    ASSERT_TRUE(snapuserd_->InitCowDevice());
-}
-
-void CowSnapuserdMetadataTest::Setup() {
-    CreateCowDevice();
-    InitMetadata();
-}
-
-void CowSnapuserdMetadataTest::ValidateMetadata() {
-    int area_sz = snapuserd_->GetMetadataAreaSize();
-    ASSERT_EQ(area_sz, 3);
-
-    size_t old_chunk;
-    size_t new_chunk;
-
-    for (int i = 0; i < area_sz; i++) {
-        void* buffer = snapuserd_->GetExceptionBuffer(i);
-        loff_t offset = 0;
-        if (i == 0) {
-            old_chunk = 256;
-            new_chunk = 2;
-        } else if (i == 1) {
-            old_chunk = 512;
-            new_chunk = 259;
-        }
-        for (int j = 0; j < 256; j++) {
-            struct disk_exception* de =
-                    reinterpret_cast<struct disk_exception*>((char*)buffer + offset);
-
-            if (i != 2) {
-                ASSERT_EQ(de->old_chunk, old_chunk);
-                ASSERT_EQ(de->new_chunk, new_chunk);
-                old_chunk += 1;
-                new_chunk += 1;
-            } else {
-                break;
-            }
-            offset += sizeof(struct disk_exception);
-        }
-
-        if (i == 2) {
-            // The first 5 copy operation is not batch merged
-            // as the sequence is discontiguous
-            struct disk_exception* de =
-                    reinterpret_cast<struct disk_exception*>((char*)buffer + offset);
-            ASSERT_EQ(de->old_chunk, 30);
-            ASSERT_EQ(de->new_chunk, 518);
-            offset += sizeof(struct disk_exception);
-
-            de = reinterpret_cast<struct disk_exception*>((char*)buffer + offset);
-            ASSERT_EQ(de->old_chunk, 25);
-            ASSERT_EQ(de->new_chunk, 520);
-            offset += sizeof(struct disk_exception);
-
-            de = reinterpret_cast<struct disk_exception*>((char*)buffer + offset);
-            ASSERT_EQ(de->old_chunk, 100);
-            ASSERT_EQ(de->new_chunk, 521);
-            offset += sizeof(struct disk_exception);
-
-            de = reinterpret_cast<struct disk_exception*>((char*)buffer + offset);
-            ASSERT_EQ(de->old_chunk, 105);
-            ASSERT_EQ(de->new_chunk, 522);
-            offset += sizeof(struct disk_exception);
-
-            de = reinterpret_cast<struct disk_exception*>((char*)buffer + offset);
-            ASSERT_EQ(de->old_chunk, 110);
-            ASSERT_EQ(de->new_chunk, 523);
-            offset += sizeof(struct disk_exception);
-
-            // The next 4 operations are batch merged as
-            // both old and new chunk are contiguous
-            de = reinterpret_cast<struct disk_exception*>((char*)buffer + offset);
-            ASSERT_EQ(de->old_chunk, 53);
-            ASSERT_EQ(de->new_chunk, 524);
-            offset += sizeof(struct disk_exception);
-
-            de = reinterpret_cast<struct disk_exception*>((char*)buffer + offset);
-            ASSERT_EQ(de->old_chunk, 52);
-            ASSERT_EQ(de->new_chunk, 525);
-            offset += sizeof(struct disk_exception);
-
-            de = reinterpret_cast<struct disk_exception*>((char*)buffer + offset);
-            ASSERT_EQ(de->old_chunk, 51);
-            ASSERT_EQ(de->new_chunk, 526);
-            offset += sizeof(struct disk_exception);
-
-            de = reinterpret_cast<struct disk_exception*>((char*)buffer + offset);
-            ASSERT_EQ(de->old_chunk, 50);
-            ASSERT_EQ(de->new_chunk, 527);
-            offset += sizeof(struct disk_exception);
-
-            // This is handling overlap operation with
-            // two batch merge operations.
-            de = reinterpret_cast<struct disk_exception*>((char*)buffer + offset);
-            ASSERT_EQ(de->old_chunk, 18);
-            ASSERT_EQ(de->new_chunk, 528);
-            offset += sizeof(struct disk_exception);
-
-            de = reinterpret_cast<struct disk_exception*>((char*)buffer + offset);
-            ASSERT_EQ(de->old_chunk, 19);
-            ASSERT_EQ(de->new_chunk, 529);
-            offset += sizeof(struct disk_exception);
-
-            de = reinterpret_cast<struct disk_exception*>((char*)buffer + offset);
-            ASSERT_EQ(de->old_chunk, 20);
-            ASSERT_EQ(de->new_chunk, 530);
-            offset += sizeof(struct disk_exception);
-
-            de = reinterpret_cast<struct disk_exception*>((char*)buffer + offset);
-            ASSERT_EQ(de->old_chunk, 21);
-            ASSERT_EQ(de->new_chunk, 532);
-            offset += sizeof(struct disk_exception);
-
-            de = reinterpret_cast<struct disk_exception*>((char*)buffer + offset);
-            ASSERT_EQ(de->old_chunk, 22);
-            ASSERT_EQ(de->new_chunk, 533);
-            offset += sizeof(struct disk_exception);
-
-            de = reinterpret_cast<struct disk_exception*>((char*)buffer + offset);
-            ASSERT_EQ(de->old_chunk, 23);
-            ASSERT_EQ(de->new_chunk, 534);
-            offset += sizeof(struct disk_exception);
-
-            // End of metadata
-            de = reinterpret_cast<struct disk_exception*>((char*)buffer + offset);
-            ASSERT_EQ(de->old_chunk, 0);
-            ASSERT_EQ(de->new_chunk, 0);
-            offset += sizeof(struct disk_exception);
-        }
-    }
-}
-
-TEST(Snapuserd_Test, Snapshot_Metadata) {
-    CowSnapuserdMetadataTest harness;
-    harness.Setup();
-    harness.ValidateMetadata();
-}
-
-TEST(Snapuserd_Test, Snapshot_Metadata_Overlap) {
-    CowSnapuserdMetadataTest harness;
-    harness.SetupPartialArea();
-    harness.ValidatePartialFilledArea();
-}
-
-TEST(Snapuserd_Test, Snapshot_Merge_Resume) {
-    CowSnapuserdTest harness;
-    ASSERT_TRUE(harness.Setup());
-    harness.MergeInterrupt();
-    harness.ValidateMerge();
-    harness.Shutdown();
-}
-
-TEST(Snapuserd_Test, Snapshot_IO_TEST) {
-    CowSnapuserdTest harness;
-    ASSERT_TRUE(harness.Setup());
-    harness.ReadSnapshotDeviceAndValidate();
-    ASSERT_TRUE(harness.Merge());
-    harness.ValidateMerge();
-    harness.Shutdown();
-}
-
-TEST(Snapuserd_Test, Snapshot_END_IO_TEST) {
-    CowSnapuserdTest harness;
-    harness.ReadLastBlock();
-    harness.Shutdown();
-}
-
-TEST(Snapuserd_Test, Snapshot_COPY_Overlap_TEST_1) {
-    CowSnapuserdTest harness;
-    ASSERT_TRUE(harness.SetupCopyOverlap_1());
-    ASSERT_TRUE(harness.Merge());
-    harness.ValidateMerge();
-    harness.Shutdown();
-}
-
-TEST(Snapuserd_Test, Snapshot_COPY_Overlap_TEST_2) {
-    CowSnapuserdTest harness;
-    ASSERT_TRUE(harness.SetupCopyOverlap_2());
-    ASSERT_TRUE(harness.Merge());
-    harness.ValidateMerge();
-    harness.Shutdown();
-}
-
-TEST(Snapuserd_Test, Snapshot_COPY_Overlap_Merge_Resume_TEST) {
-    CowSnapuserdTest harness;
-    ASSERT_TRUE(harness.SetupCopyOverlap_1());
-    harness.MergeInterrupt();
-    harness.ValidateMerge();
-    harness.Shutdown();
-}
-
-TEST(Snapuserd_Test, ReadDmUserBlockWithoutDaemon) {
-    CowSnapuserdTest harness;
-    harness.ReadDmUserBlockWithoutDaemon();
-}
-
-TEST(Snapuserd_Test, Snapshot_Merge_Crash_Fixed_Ordered) {
-    CowSnapuserdTest harness;
-    ASSERT_TRUE(harness.SetupOrderedOps());
-    harness.MergeInterruptFixed(300);
-    harness.ValidateMerge();
-    harness.Shutdown();
-}
-
-TEST(Snapuserd_Test, Snapshot_Merge_Crash_Random_Ordered) {
-    CowSnapuserdTest harness;
-    ASSERT_TRUE(harness.SetupOrderedOps());
-    harness.MergeInterruptRandomly(500);
-    harness.ValidateMerge();
-    harness.Shutdown();
-}
-
-TEST(Snapuserd_Test, Snapshot_Merge_Crash_Fixed_Inverted) {
-    CowSnapuserdTest harness;
-    ASSERT_TRUE(harness.SetupOrderedOpsInverted());
-    harness.MergeInterruptFixed(50);
-    harness.ValidateMerge();
-    harness.Shutdown();
-}
-
-TEST(Snapuserd_Test, Snapshot_Merge_Crash_Random_Inverted) {
-    CowSnapuserdTest harness;
-    ASSERT_TRUE(harness.SetupOrderedOpsInverted());
-    harness.MergeInterruptRandomly(50);
-    harness.ValidateMerge();
-    harness.Shutdown();
-}
-
-}  // namespace snapshot
-}  // namespace android
-
-int main(int argc, char** argv) {
-    ::testing::InitGoogleTest(&argc, argv);
-    return RUN_ALL_TESTS();
-}
diff --git a/fs_mgr/libsnapshot/snapuserd/dm-snapshot-merge/snapuserd.cpp b/fs_mgr/libsnapshot/snapuserd/dm-snapshot-merge/snapuserd.cpp
deleted file mode 100644
index 93bb0b2..0000000
--- a/fs_mgr/libsnapshot/snapuserd/dm-snapshot-merge/snapuserd.cpp
+++ /dev/null
@@ -1,870 +0,0 @@
-/*
- * Copyright (C) 2020 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-#include "snapuserd.h"
-
-#include <dirent.h>
-#include <fcntl.h>
-#include <linux/fs.h>
-#include <unistd.h>
-#include <algorithm>
-
-#include <csignal>
-#include <optional>
-#include <set>
-
-#include <android-base/file.h>
-#include <android-base/logging.h>
-#include <android-base/parseint.h>
-#include <android-base/properties.h>
-#include <android-base/strings.h>
-#include <android-base/unique_fd.h>
-#include <snapuserd/snapuserd_client.h>
-
-namespace android {
-namespace snapshot {
-
-using namespace android;
-using namespace android::dm;
-using android::base::unique_fd;
-
-#define SNAP_LOG(level) LOG(level) << misc_name_ << ": "
-#define SNAP_PLOG(level) PLOG(level) << misc_name_ << ": "
-
-Snapuserd::Snapuserd(const std::string& misc_name, const std::string& cow_device,
-                     const std::string& backing_device) {
-    misc_name_ = misc_name;
-    cow_device_ = cow_device;
-    backing_store_device_ = backing_device;
-    control_device_ = "/dev/dm-user/" + misc_name;
-}
-
-bool Snapuserd::InitializeWorkers() {
-    for (int i = 0; i < NUM_THREADS_PER_PARTITION; i++) {
-        std::unique_ptr<WorkerThread> wt = std::make_unique<WorkerThread>(
-                cow_device_, backing_store_device_, control_device_, misc_name_, GetSharedPtr());
-
-        worker_threads_.push_back(std::move(wt));
-    }
-
-    read_ahead_thread_ = std::make_unique<ReadAheadThread>(cow_device_, backing_store_device_,
-                                                           misc_name_, GetSharedPtr());
-    return true;
-}
-
-std::unique_ptr<CowReader> Snapuserd::CloneReaderForWorker() {
-    return reader_->CloneCowReader();
-}
-
-bool Snapuserd::CommitMerge(int num_merge_ops) {
-    struct CowHeader* ch = reinterpret_cast<struct CowHeader*>(mapped_addr_);
-    ch->num_merge_ops += num_merge_ops;
-
-    if (read_ahead_feature_ && read_ahead_ops_.size() > 0) {
-        struct BufferState* ra_state = GetBufferState();
-        ra_state->read_ahead_state = kCowReadAheadInProgress;
-    }
-
-    int ret = msync(mapped_addr_, BLOCK_SZ, MS_SYNC);
-    if (ret < 0) {
-        SNAP_PLOG(ERROR) << "msync header failed: " << ret;
-        return false;
-    }
-
-    merge_initiated_ = true;
-
-    return true;
-}
-
-void Snapuserd::PrepareReadAhead() {
-    if (!read_ahead_feature_) {
-        return;
-    }
-
-    struct BufferState* ra_state = GetBufferState();
-    // Check if the data has to be re-constructed from COW device
-    if (ra_state->read_ahead_state == kCowReadAheadDone) {
-        populate_data_from_cow_ = true;
-    } else {
-        populate_data_from_cow_ = false;
-    }
-
-    StartReadAhead();
-}
-
-bool Snapuserd::GetRABuffer(std::unique_lock<std::mutex>* lock, uint64_t block, void* buffer) {
-    if (!lock->owns_lock()) {
-        SNAP_LOG(ERROR) << "GetRABuffer - Lock not held";
-        return false;
-    }
-    std::unordered_map<uint64_t, void*>::iterator it = read_ahead_buffer_map_.find(block);
-
-    // This will be true only for IO's generated as part of reading a root
-    // filesystem. IO's related to merge should always be in read-ahead cache.
-    if (it == read_ahead_buffer_map_.end()) {
-        return false;
-    }
-
-    // Theoretically, we can send the data back from the read-ahead buffer
-    // all the way to the kernel without memcpy. However, if the IO is
-    // un-aligned, the wrapper function will need to touch the read-ahead
-    // buffers and transitions will be bit more complicated.
-    memcpy(buffer, it->second, BLOCK_SZ);
-    return true;
-}
-
-// ========== State transition functions for read-ahead operations ===========
-
-bool Snapuserd::GetReadAheadPopulatedBuffer(uint64_t block, void* buffer) {
-    if (!read_ahead_feature_) {
-        return false;
-    }
-
-    {
-        std::unique_lock<std::mutex> lock(lock_);
-        if (io_state_ == READ_AHEAD_IO_TRANSITION::READ_AHEAD_FAILURE) {
-            return false;
-        }
-
-        if (io_state_ == READ_AHEAD_IO_TRANSITION::IO_IN_PROGRESS) {
-            return GetRABuffer(&lock, block, buffer);
-        }
-    }
-
-    {
-        // Read-ahead thread IO is in-progress. Wait for it to complete
-        std::unique_lock<std::mutex> lock(lock_);
-        while (!(io_state_ == READ_AHEAD_IO_TRANSITION::READ_AHEAD_FAILURE ||
-                 io_state_ == READ_AHEAD_IO_TRANSITION::IO_IN_PROGRESS)) {
-            cv.wait(lock);
-        }
-
-        return GetRABuffer(&lock, block, buffer);
-    }
-}
-
-// This is invoked by read-ahead thread waiting for merge IO's
-// to complete
-bool Snapuserd::WaitForMergeToComplete() {
-    {
-        std::unique_lock<std::mutex> lock(lock_);
-        while (!(io_state_ == READ_AHEAD_IO_TRANSITION::READ_AHEAD_BEGIN ||
-                 io_state_ == READ_AHEAD_IO_TRANSITION::IO_TERMINATED)) {
-            cv.wait(lock);
-        }
-
-        if (io_state_ == READ_AHEAD_IO_TRANSITION::IO_TERMINATED) {
-            return false;
-        }
-
-        io_state_ = READ_AHEAD_IO_TRANSITION::READ_AHEAD_IN_PROGRESS;
-        return true;
-    }
-}
-
-// This is invoked during the launch of worker threads. We wait
-// for read-ahead thread to by fully up before worker threads
-// are launched; else we will have a race between worker threads
-// and read-ahead thread specifically during re-construction.
-bool Snapuserd::WaitForReadAheadToStart() {
-    {
-        std::unique_lock<std::mutex> lock(lock_);
-        while (!(io_state_ == READ_AHEAD_IO_TRANSITION::IO_IN_PROGRESS ||
-                 io_state_ == READ_AHEAD_IO_TRANSITION::READ_AHEAD_FAILURE)) {
-            cv.wait(lock);
-        }
-
-        if (io_state_ == READ_AHEAD_IO_TRANSITION::READ_AHEAD_FAILURE) {
-            return false;
-        }
-
-        return true;
-    }
-}
-
-// Invoked by worker threads when a sequence of merge operation
-// is complete notifying read-ahead thread to make forward
-// progress.
-void Snapuserd::StartReadAhead() {
-    {
-        std::lock_guard<std::mutex> lock(lock_);
-        io_state_ = READ_AHEAD_IO_TRANSITION::READ_AHEAD_BEGIN;
-    }
-
-    cv.notify_one();
-}
-
-void Snapuserd::MergeCompleted() {
-    {
-        std::lock_guard<std::mutex> lock(lock_);
-        io_state_ = READ_AHEAD_IO_TRANSITION::IO_TERMINATED;
-    }
-
-    cv.notify_one();
-}
-
-bool Snapuserd::ReadAheadIOCompleted(bool sync) {
-    if (sync) {
-        // Flush the entire buffer region
-        int ret = msync(mapped_addr_, total_mapped_addr_length_, MS_SYNC);
-        if (ret < 0) {
-            PLOG(ERROR) << "msync failed after ReadAheadIOCompleted: " << ret;
-            return false;
-        }
-
-        // Metadata and data are synced. Now, update the state.
-        // We need to update the state after flushing data; if there is a crash
-        // when read-ahead IO is in progress, the state of data in the COW file
-        // is unknown. kCowReadAheadDone acts as a checkpoint wherein the data
-        // in the scratch space is good and during next reboot, read-ahead thread
-        // can safely re-construct the data.
-        struct BufferState* ra_state = GetBufferState();
-        ra_state->read_ahead_state = kCowReadAheadDone;
-
-        ret = msync(mapped_addr_, BLOCK_SZ, MS_SYNC);
-        if (ret < 0) {
-            PLOG(ERROR) << "msync failed to flush Readahead completion state...";
-            return false;
-        }
-    }
-
-    // Notify the worker threads
-    {
-        std::lock_guard<std::mutex> lock(lock_);
-        io_state_ = READ_AHEAD_IO_TRANSITION::IO_IN_PROGRESS;
-    }
-
-    cv.notify_all();
-    return true;
-}
-
-void Snapuserd::ReadAheadIOFailed() {
-    {
-        std::lock_guard<std::mutex> lock(lock_);
-        io_state_ = READ_AHEAD_IO_TRANSITION::READ_AHEAD_FAILURE;
-    }
-
-    cv.notify_all();
-}
-
-//========== End of state transition functions ====================
-
-bool Snapuserd::IsChunkIdMetadata(chunk_t chunk) {
-    uint32_t stride = exceptions_per_area_ + 1;
-    lldiv_t divresult = lldiv(chunk, stride);
-
-    return (divresult.rem == NUM_SNAPSHOT_HDR_CHUNKS);
-}
-
-// Find the next free chunk-id to be assigned. Check if the next free
-// chunk-id represents a metadata page. If so, skip it.
-chunk_t Snapuserd::GetNextAllocatableChunkId(chunk_t chunk) {
-    chunk_t next_chunk = chunk + 1;
-
-    if (IsChunkIdMetadata(next_chunk)) {
-        next_chunk += 1;
-    }
-    return next_chunk;
-}
-
-void Snapuserd::CheckMergeCompletionStatus() {
-    if (!merge_initiated_) {
-        SNAP_LOG(INFO) << "Merge was not initiated. Total-data-ops: "
-                       << reader_->get_num_total_data_ops();
-        return;
-    }
-
-    struct CowHeader* ch = reinterpret_cast<struct CowHeader*>(mapped_addr_);
-
-    SNAP_LOG(INFO) << "Merge-status: Total-Merged-ops: " << ch->num_merge_ops
-                   << " Total-data-ops: " << reader_->get_num_total_data_ops();
-}
-
-/*
- * Read the metadata from COW device and
- * construct the metadata as required by the kernel.
- *
- * Please see design on kernel COW format
- *
- * 1: Read the metadata from internal COW device
- * 2: There are 3 COW operations:
- *     a: Replace op
- *     b: Copy op
- *     c: Zero op
- * 3: For each of the 3 operations, op->new_block
- *    represents the block number in the base device
- *    for which one of the 3 operations have to be applied.
- *    This represents the old_chunk in the kernel COW format
- * 4: We need to assign new_chunk for a corresponding old_chunk
- * 5: The algorithm is similar to how kernel assigns chunk number
- *    while creating exceptions. However, there are few cases
- *    which needs to be addressed here:
- *      a: During merge process, kernel scans the metadata page
- *      from backwards when merge is initiated. Since, we need
- *      to make sure that the merge ordering follows our COW format,
- *      we read the COW operation from backwards and populate the
- *      metadata so that when kernel starts the merging from backwards,
- *      those ops correspond to the beginning of our COW format.
- *      b: Kernel can merge successive operations if the two chunk IDs
- *      are contiguous. This can be problematic when there is a crash
- *      during merge; specifically when the merge operation has dependency.
- *      These dependencies can only happen during copy operations.
- *
- *      To avoid this problem, we make sure overlap copy operations
- *      are not batch merged.
- * 6: Use a monotonically increasing chunk number to assign the
- *    new_chunk
- * 7: Each chunk-id represents either
- *        a: Metadata page or
- *        b: Data page
- * 8: Chunk-id representing a data page is stored in a map.
- * 9: Chunk-id representing a metadata page is converted into a vector
- *    index. We store this in vector as kernel requests metadata during
- *    two stage:
- *       a: When initial dm-snapshot device is created, kernel requests
- *          all the metadata and stores it in its internal data-structures.
- *       b: During merge, kernel once again requests the same metadata
- *          once-again.
- *    In both these cases, a quick lookup based on chunk-id is done.
- * 10: When chunk number is incremented, we need to make sure that
- *    if the chunk is representing a metadata page and skip.
- * 11: Each 4k page will contain 256 disk exceptions. We call this
- *    exceptions_per_area_
- * 12: Kernel will stop issuing metadata IO request when new-chunk ID is 0.
- */
-bool Snapuserd::ReadMetadata() {
-    reader_ = std::make_unique<CowReader>();
-    CowOptions options;
-    bool metadata_found = false;
-    int replace_ops = 0, zero_ops = 0, copy_ops = 0;
-
-    SNAP_LOG(DEBUG) << "ReadMetadata: Parsing cow file";
-
-    if (!reader_->Parse(cow_fd_)) {
-        SNAP_LOG(ERROR) << "Failed to parse";
-        return false;
-    }
-
-    const auto& header = reader_->GetHeader();
-    if (!(header.block_size == BLOCK_SZ)) {
-        SNAP_LOG(ERROR) << "Invalid header block size found: " << header.block_size;
-        return false;
-    }
-
-    SNAP_LOG(DEBUG) << "Merge-ops: " << header.num_merge_ops;
-
-    if (!MmapMetadata()) {
-        SNAP_LOG(ERROR) << "mmap failed";
-        return false;
-    }
-
-    // Initialize the iterator for reading metadata
-    std::unique_ptr<ICowOpIter> cowop_rm_iter = reader_->GetRevMergeOpIter();
-
-    exceptions_per_area_ = (CHUNK_SIZE << SECTOR_SHIFT) / sizeof(struct disk_exception);
-
-    // Start from chunk number 2. Chunk 0 represents header and chunk 1
-    // represents first metadata page.
-    chunk_t data_chunk_id = NUM_SNAPSHOT_HDR_CHUNKS + 1;
-    size_t num_ops = 0;
-
-    loff_t offset = 0;
-    std::unique_ptr<uint8_t[]> de_ptr =
-            std::make_unique<uint8_t[]>(exceptions_per_area_ * sizeof(struct disk_exception));
-
-    // This memset is important. Kernel will stop issuing IO when new-chunk ID
-    // is 0. When Area is not filled completely with all 256 exceptions,
-    // this memset will ensure that metadata read is completed.
-    memset(de_ptr.get(), 0, (exceptions_per_area_ * sizeof(struct disk_exception)));
-
-    while (!cowop_rm_iter->AtEnd()) {
-        const CowOperation* cow_op = cowop_rm_iter->Get();
-        struct disk_exception* de =
-                reinterpret_cast<struct disk_exception*>((char*)de_ptr.get() + offset);
-
-        metadata_found = true;
-        // This loop will handle all the replace and zero ops.
-        // We will handle the copy ops later as it requires special
-        // handling of assigning chunk-id's. Furthermore, we make
-        // sure that replace/zero and copy ops are not batch merged; hence,
-        // the bump in the chunk_id before break of this loop
-        if (IsOrderedOp(*cow_op)) {
-            data_chunk_id = GetNextAllocatableChunkId(data_chunk_id);
-            break;
-        }
-
-        if (cow_op->type() == kCowReplaceOp) {
-            replace_ops++;
-        } else if (cow_op->type() == kCowZeroOp) {
-            zero_ops++;
-        }
-
-        // Construct the disk-exception
-        de->old_chunk = cow_op->new_block;
-        de->new_chunk = data_chunk_id;
-
-        // Store operation pointer.
-        chunk_vec_.push_back(std::make_pair(ChunkToSector(data_chunk_id), cow_op));
-        num_ops += 1;
-        offset += sizeof(struct disk_exception);
-        cowop_rm_iter->Next();
-
-        SNAP_LOG(DEBUG) << num_ops << ":"
-                        << " Old-chunk: " << de->old_chunk << " New-chunk: " << de->new_chunk;
-
-        if (num_ops == exceptions_per_area_) {
-            // Store it in vector at the right index. This maps the chunk-id to
-            // vector index.
-            vec_.push_back(std::move(de_ptr));
-            offset = 0;
-            num_ops = 0;
-
-            // Create buffer for next area
-            de_ptr = std::make_unique<uint8_t[]>(exceptions_per_area_ *
-                                                 sizeof(struct disk_exception));
-            memset(de_ptr.get(), 0, (exceptions_per_area_ * sizeof(struct disk_exception)));
-
-            if (cowop_rm_iter->AtEnd()) {
-                vec_.push_back(std::move(de_ptr));
-            }
-        }
-
-        data_chunk_id = GetNextAllocatableChunkId(data_chunk_id);
-    }
-
-    int num_ra_ops_per_iter = ((GetBufferDataSize()) / BLOCK_SZ);
-    std::optional<chunk_t> prev_id = {};
-    std::vector<const CowOperation*> vec;
-    std::set<uint64_t> dest_blocks;
-    std::set<uint64_t> source_blocks;
-    size_t pending_ordered_ops = exceptions_per_area_ - num_ops;
-    uint64_t total_ordered_ops = reader_->get_num_ordered_ops_to_merge();
-
-    SNAP_LOG(DEBUG) << " Processing copy-ops at Area: " << vec_.size()
-                    << " Number of replace/zero ops completed in this area: " << num_ops
-                    << " Pending copy ops for this area: " << pending_ordered_ops;
-
-    while (!cowop_rm_iter->AtEnd()) {
-        do {
-            const CowOperation* cow_op = cowop_rm_iter->Get();
-
-            // We have two cases specific cases:
-            //
-            // =====================================================
-            // Case 1: Overlapping copy regions
-            //
-            // Ex:
-            //
-            // Source -> Destination
-            //
-            // 1: 15 -> 18
-            // 2: 16 -> 19
-            // 3: 17 -> 20
-            // 4: 18 -> 21
-            // 5: 19 -> 22
-            // 6: 20 -> 23
-            //
-            // We have 6 copy operations to be executed in OTA and there is a overlap. Update-engine
-            // will write to COW file as follows:
-            //
-            // Op-1: 20 -> 23
-            // Op-2: 19 -> 22
-            // Op-3: 18 -> 21
-            // Op-4: 17 -> 20
-            // Op-5: 16 -> 19
-            // Op-6: 15 -> 18
-            //
-            // Note that the blocks numbers are contiguous. Hence, all 6 copy
-            // operations can be batch merged. However, that will be
-            // problematic if we have a crash as block 20, 19, 18 would have
-            // been overwritten and hence subsequent recovery may end up with
-            // a silent data corruption when op-1, op-2 and op-3 are
-            // re-executed.
-            //
-            // To address the above problem, read-ahead thread will
-            // read all the 6 source blocks, cache them in the scratch
-            // space of the COW file. During merge, read-ahead
-            // thread will serve the blocks from the read-ahead cache.
-            // If there is a crash during merge; on subsequent reboot,
-            // read-ahead thread will recover the data from the
-            // scratch space and re-construct it thereby there
-            // is no loss of data.
-            //
-            // Note that we will follow the same order of COW operations
-            // as present in the COW file. This will make sure that
-            // the merge of operations are done based on the ops present
-            // in the file.
-            //===========================================================
-            uint64_t block_source = cow_op->source();
-            if (prev_id.has_value()) {
-                if (dest_blocks.count(cow_op->new_block) || source_blocks.count(block_source)) {
-                    break;
-                }
-            }
-            metadata_found = true;
-            pending_ordered_ops -= 1;
-            vec.push_back(cow_op);
-            dest_blocks.insert(block_source);
-            source_blocks.insert(cow_op->new_block);
-            prev_id = cow_op->new_block;
-            cowop_rm_iter->Next();
-        } while (!cowop_rm_iter->AtEnd() && pending_ordered_ops);
-
-        data_chunk_id = GetNextAllocatableChunkId(data_chunk_id);
-        SNAP_LOG(DEBUG) << "Batch Merge copy-ops of size: " << vec.size()
-                        << " Area: " << vec_.size() << " Area offset: " << offset
-                        << " Pending-ordered-ops in this area: " << pending_ordered_ops;
-
-        for (size_t i = 0; i < vec.size(); i++) {
-            struct disk_exception* de =
-                    reinterpret_cast<struct disk_exception*>((char*)de_ptr.get() + offset);
-            const CowOperation* cow_op = vec[i];
-
-            de->old_chunk = cow_op->new_block;
-            de->new_chunk = data_chunk_id;
-
-            // Store operation pointer.
-            chunk_vec_.push_back(std::make_pair(ChunkToSector(data_chunk_id), cow_op));
-            offset += sizeof(struct disk_exception);
-            num_ops += 1;
-            if (cow_op->type() == kCowCopyOp) {
-                copy_ops++;
-            }
-
-            if (read_ahead_feature_) {
-                read_ahead_ops_.push_back(cow_op);
-            }
-
-            SNAP_LOG(DEBUG) << num_ops << ":"
-                            << " Ordered-op: "
-                            << " Old-chunk: " << de->old_chunk << " New-chunk: " << de->new_chunk;
-
-            if (num_ops == exceptions_per_area_) {
-                // Store it in vector at the right index. This maps the chunk-id to
-                // vector index.
-                vec_.push_back(std::move(de_ptr));
-                num_ops = 0;
-                offset = 0;
-
-                // Create buffer for next area
-                de_ptr = std::make_unique<uint8_t[]>(exceptions_per_area_ *
-                                                     sizeof(struct disk_exception));
-                memset(de_ptr.get(), 0, (exceptions_per_area_ * sizeof(struct disk_exception)));
-
-                if (cowop_rm_iter->AtEnd()) {
-                    vec_.push_back(std::move(de_ptr));
-                    SNAP_LOG(DEBUG) << "ReadMetadata() completed; Number of Areas: " << vec_.size();
-                }
-
-                if (!(pending_ordered_ops == 0)) {
-                    SNAP_LOG(ERROR) << "Invalid pending_ordered_ops: expected: 0 found: "
-                                    << pending_ordered_ops;
-                    return false;
-                }
-                pending_ordered_ops = exceptions_per_area_;
-            }
-
-            data_chunk_id = GetNextAllocatableChunkId(data_chunk_id);
-            total_ordered_ops -= 1;
-            /*
-             * Split the number of ops based on the size of read-ahead buffer
-             * region. We need to ensure that kernel doesn't issue IO on blocks
-             * which are not read by the read-ahead thread.
-             */
-            if (read_ahead_feature_ && (total_ordered_ops % num_ra_ops_per_iter == 0)) {
-                data_chunk_id = GetNextAllocatableChunkId(data_chunk_id);
-            }
-        }
-        vec.clear();
-        dest_blocks.clear();
-        source_blocks.clear();
-        prev_id.reset();
-    }
-
-    // Partially filled area or there is no metadata
-    // If there is no metadata, fill with zero so that kernel
-    // is aware that merge is completed.
-    if (num_ops || !metadata_found) {
-        vec_.push_back(std::move(de_ptr));
-        SNAP_LOG(DEBUG) << "ReadMetadata() completed. Partially filled area num_ops: " << num_ops
-                        << "Areas : " << vec_.size();
-    }
-
-    chunk_vec_.shrink_to_fit();
-    vec_.shrink_to_fit();
-    read_ahead_ops_.shrink_to_fit();
-
-    // Sort the vector based on sectors as we need this during un-aligned access
-    std::sort(chunk_vec_.begin(), chunk_vec_.end(), compare);
-
-    SNAP_LOG(INFO) << "ReadMetadata completed. Final-chunk-id: " << data_chunk_id
-                   << " Num Sector: " << ChunkToSector(data_chunk_id)
-                   << " Replace-ops: " << replace_ops << " Zero-ops: " << zero_ops
-                   << " Copy-ops: " << copy_ops << " Areas: " << vec_.size()
-                   << " Num-ops-merged: " << header.num_merge_ops
-                   << " Total-data-ops: " << reader_->get_num_total_data_ops();
-
-    // Total number of sectors required for creating dm-user device
-    num_sectors_ = ChunkToSector(data_chunk_id);
-    merge_initiated_ = false;
-    PrepareReadAhead();
-
-    return true;
-}
-
-bool Snapuserd::MmapMetadata() {
-    const auto& header = reader_->GetHeader();
-
-    if (header.prefix.major_version >= 2 && header.buffer_size > 0) {
-        total_mapped_addr_length_ = header.prefix.header_size + BUFFER_REGION_DEFAULT_SIZE;
-        read_ahead_feature_ = true;
-    } else {
-        // mmap the first 4k page - older COW format
-        total_mapped_addr_length_ = BLOCK_SZ;
-        read_ahead_feature_ = false;
-    }
-
-    mapped_addr_ = mmap(NULL, total_mapped_addr_length_, PROT_READ | PROT_WRITE, MAP_SHARED,
-                        cow_fd_.get(), 0);
-    if (mapped_addr_ == MAP_FAILED) {
-        SNAP_LOG(ERROR) << "mmap metadata failed";
-        return false;
-    }
-
-    return true;
-}
-
-void Snapuserd::UnmapBufferRegion() {
-    int ret = munmap(mapped_addr_, total_mapped_addr_length_);
-    if (ret < 0) {
-        SNAP_PLOG(ERROR) << "munmap failed";
-    }
-}
-
-void MyLogger(android::base::LogId, android::base::LogSeverity severity, const char*, const char*,
-              unsigned int, const char* message) {
-    if (severity == android::base::ERROR) {
-        fprintf(stderr, "%s\n", message);
-    } else {
-        fprintf(stdout, "%s\n", message);
-    }
-}
-
-bool Snapuserd::InitCowDevice() {
-    cow_fd_.reset(open(cow_device_.c_str(), O_RDWR));
-    if (cow_fd_ < 0) {
-        SNAP_PLOG(ERROR) << "Open Failed: " << cow_device_;
-        return false;
-    }
-
-    return ReadMetadata();
-}
-
-void Snapuserd::ReadBlocksToCache(const std::string& dm_block_device,
-                                  const std::string& partition_name, off_t offset, size_t size) {
-    android::base::unique_fd fd(TEMP_FAILURE_RETRY(open(dm_block_device.c_str(), O_RDONLY)));
-    if (fd.get() == -1) {
-        SNAP_PLOG(ERROR) << "Error reading " << dm_block_device
-                         << " partition-name: " << partition_name;
-        return;
-    }
-
-    size_t remain = size;
-    off_t file_offset = offset;
-    // We pick 4M I/O size based on the fact that the current
-    // update_verifier has a similar I/O size.
-    size_t read_sz = 1024 * BLOCK_SZ;
-    std::vector<uint8_t> buf(read_sz);
-
-    while (remain > 0) {
-        size_t to_read = std::min(remain, read_sz);
-
-        if (!android::base::ReadFullyAtOffset(fd.get(), buf.data(), to_read, file_offset)) {
-            SNAP_PLOG(ERROR) << "Failed to read block from block device: " << dm_block_device
-                             << " at offset: " << file_offset
-                             << " partition-name: " << partition_name << " total-size: " << size
-                             << " remain_size: " << remain;
-            return;
-        }
-
-        file_offset += to_read;
-        remain -= to_read;
-    }
-
-    SNAP_LOG(INFO) << "Finished reading block-device: " << dm_block_device
-                   << " partition: " << partition_name << " size: " << size
-                   << " offset: " << offset;
-}
-
-void Snapuserd::ReadBlocks(const std::string& partition_name, const std::string& dm_block_device) {
-    SNAP_LOG(DEBUG) << "Reading partition: " << partition_name
-                    << " Block-Device: " << dm_block_device;
-
-    uint64_t dev_sz = 0;
-
-    unique_fd fd(TEMP_FAILURE_RETRY(open(dm_block_device.c_str(), O_RDONLY | O_CLOEXEC)));
-    if (fd < 0) {
-        SNAP_LOG(ERROR) << "Cannot open block device";
-        return;
-    }
-
-    dev_sz = get_block_device_size(fd.get());
-    if (!dev_sz) {
-        SNAP_PLOG(ERROR) << "Could not determine block device size: " << dm_block_device;
-        return;
-    }
-
-    int num_threads = 2;
-    size_t num_blocks = dev_sz >> BLOCK_SHIFT;
-    size_t num_blocks_per_thread = num_blocks / num_threads;
-    size_t read_sz_per_thread = num_blocks_per_thread << BLOCK_SHIFT;
-    off_t offset = 0;
-
-    for (int i = 0; i < num_threads; i++) {
-        (void)std::async(std::launch::async, &Snapuserd::ReadBlocksToCache, this, dm_block_device,
-                         partition_name, offset, read_sz_per_thread);
-
-        offset += read_sz_per_thread;
-    }
-}
-
-/*
- * Entry point to launch threads
- */
-bool Snapuserd::Start() {
-    std::vector<std::future<bool>> threads;
-    std::future<bool> ra_thread;
-    bool rathread = (read_ahead_feature_ && (read_ahead_ops_.size() > 0));
-
-    // Start the read-ahead thread and wait
-    // for it as the data has to be re-constructed
-    // from COW device.
-    if (rathread) {
-        ra_thread = std::async(std::launch::async, &ReadAheadThread::RunThread,
-                               read_ahead_thread_.get());
-        if (!WaitForReadAheadToStart()) {
-            SNAP_LOG(ERROR) << "Failed to start Read-ahead thread...";
-            return false;
-        }
-
-        SNAP_LOG(INFO) << "Read-ahead thread started...";
-    }
-
-    // Launch worker threads
-    for (int i = 0; i < worker_threads_.size(); i++) {
-        threads.emplace_back(
-                std::async(std::launch::async, &WorkerThread::RunThread, worker_threads_[i].get()));
-    }
-
-    bool second_stage_init = true;
-
-    // We don't want to read the blocks during first stage init.
-    if (android::base::EndsWith(misc_name_, "-init") || is_socket_present_) {
-        second_stage_init = false;
-    }
-
-    if (second_stage_init) {
-        SNAP_LOG(INFO) << "Reading blocks to cache....";
-        auto& dm = DeviceMapper::Instance();
-        auto dm_block_devices = dm.FindDmPartitions();
-        if (dm_block_devices.empty()) {
-            SNAP_LOG(ERROR) << "No dm-enabled block device is found.";
-        } else {
-            auto parts = android::base::Split(misc_name_, "-");
-            std::string partition_name = parts[0];
-
-            const char* suffix_b = "_b";
-            const char* suffix_a = "_a";
-
-            partition_name.erase(partition_name.find_last_not_of(suffix_b) + 1);
-            partition_name.erase(partition_name.find_last_not_of(suffix_a) + 1);
-
-            if (dm_block_devices.find(partition_name) == dm_block_devices.end()) {
-                SNAP_LOG(ERROR) << "Failed to find dm block device for " << partition_name;
-            } else {
-                ReadBlocks(partition_name, dm_block_devices.at(partition_name));
-            }
-        }
-    } else {
-        SNAP_LOG(INFO) << "Not reading block device into cache";
-    }
-
-    bool ret = true;
-    for (auto& t : threads) {
-        ret = t.get() && ret;
-    }
-
-    if (rathread) {
-        // Notify the read-ahead thread that all worker threads
-        // are done. We need this explicit notification when
-        // there is an IO failure or there was a switch
-        // of dm-user table; thus, forcing the read-ahead
-        // thread to wake up.
-        MergeCompleted();
-        ret = ret && ra_thread.get();
-    }
-
-    return ret;
-}
-
-uint64_t Snapuserd::GetBufferMetadataOffset() {
-    const auto& header = reader_->GetHeader();
-
-    size_t size = header.prefix.header_size + sizeof(BufferState);
-    return size;
-}
-
-/*
- * Metadata for read-ahead is 16 bytes. For a 2 MB region, we will
- * end up with 8k (2 PAGE) worth of metadata. Thus, a 2MB buffer
- * region is split into:
- *
- * 1: 8k metadata
- *
- */
-size_t Snapuserd::GetBufferMetadataSize() {
-    const auto& header = reader_->GetHeader();
-
-    size_t metadata_bytes = (header.buffer_size * sizeof(struct ScratchMetadata)) / BLOCK_SZ;
-    return metadata_bytes;
-}
-
-size_t Snapuserd::GetBufferDataOffset() {
-    const auto& header = reader_->GetHeader();
-
-    return (header.prefix.header_size + GetBufferMetadataSize());
-}
-
-/*
- * (2MB - 8K = 2088960 bytes) will be the buffer region to hold the data.
- */
-size_t Snapuserd::GetBufferDataSize() {
-    const auto& header = reader_->GetHeader();
-
-    size_t size = header.buffer_size - GetBufferMetadataSize();
-    return size;
-}
-
-struct BufferState* Snapuserd::GetBufferState() {
-    const auto& header = reader_->GetHeader();
-
-    struct BufferState* ra_state =
-            reinterpret_cast<struct BufferState*>((char*)mapped_addr_ + header.prefix.header_size);
-    return ra_state;
-}
-
-}  // namespace snapshot
-}  // namespace android
diff --git a/fs_mgr/libsnapshot/snapuserd/dm-snapshot-merge/snapuserd.h b/fs_mgr/libsnapshot/snapuserd/dm-snapshot-merge/snapuserd.h
deleted file mode 100644
index beb6004..0000000
--- a/fs_mgr/libsnapshot/snapuserd/dm-snapshot-merge/snapuserd.h
+++ /dev/null
@@ -1,332 +0,0 @@
-// Copyright (C) 2020 The Android Open Source Project
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//      http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-#pragma once
-
-#include <linux/types.h>
-#include <stdint.h>
-#include <stdlib.h>
-#include <sys/mman.h>
-
-#include <bitset>
-#include <condition_variable>
-#include <csignal>
-#include <cstring>
-#include <future>
-#include <iostream>
-#include <limits>
-#include <map>
-#include <mutex>
-#include <string>
-#include <thread>
-#include <unordered_map>
-#include <unordered_set>
-#include <vector>
-
-#include <android-base/file.h>
-#include <android-base/logging.h>
-#include <android-base/stringprintf.h>
-#include <android-base/unique_fd.h>
-#include <ext4_utils/ext4_utils.h>
-#include <libdm/dm.h>
-#include <libsnapshot/cow_reader.h>
-#include <libsnapshot/cow_writer.h>
-#include <snapuserd/snapuserd_buffer.h>
-#include <snapuserd/snapuserd_kernel.h>
-
-namespace android {
-namespace snapshot {
-
-using android::base::unique_fd;
-using namespace std::chrono_literals;
-
-static constexpr size_t PAYLOAD_SIZE = (1UL << 20);
-static_assert(PAYLOAD_SIZE >= BLOCK_SZ);
-
-/*
- * With 4 threads, we get optimal performance
- * when update_verifier reads the partition during
- * boot.
- */
-static constexpr int NUM_THREADS_PER_PARTITION = 4;
-
-/*
- * State transitions between worker threads and read-ahead
- * threads.
- *
- * READ_AHEAD_BEGIN: Worker threads initiates the read-ahead
- *                   thread to begin reading the copy operations
- *                   for each bounded region.
- *
- * READ_AHEAD_IN_PROGRESS: When read ahead thread is in-flight
- *                         and reading the copy operations.
- *
- * IO_IN_PROGRESS: Merge operation is in-progress by worker threads.
- *
- * IO_TERMINATED: When all the worker threads are done, request the
- *                read-ahead thread to terminate
- *
- * READ_AHEAD_FAILURE: If there are any IO failures when read-ahead
- *                     thread is reading from COW device.
- *
- * The transition of each states is described in snapuserd_readahead.cpp
- */
-enum class READ_AHEAD_IO_TRANSITION {
-    READ_AHEAD_BEGIN,
-    READ_AHEAD_IN_PROGRESS,
-    IO_IN_PROGRESS,
-    IO_TERMINATED,
-    READ_AHEAD_FAILURE,
-};
-
-class Snapuserd;
-
-class ReadAheadThread {
-  public:
-    ReadAheadThread(const std::string& cow_device, const std::string& backing_device,
-                    const std::string& misc_name, std::shared_ptr<Snapuserd> snapuserd);
-    bool RunThread();
-
-  private:
-    void InitializeRAIter();
-    bool RAIterDone();
-    void RAIterNext();
-    const CowOperation* GetRAOpIter();
-    void InitializeBuffer();
-
-    bool InitializeFds();
-    void CloseFds() {
-        cow_fd_ = {};
-        backing_store_fd_ = {};
-    }
-
-    bool ReadAheadIOStart();
-    void PrepareReadAhead(uint64_t* source_offset, int* pending_ops, std::vector<uint64_t>& blocks);
-    bool ReconstructDataFromCow();
-    void CheckOverlap(const CowOperation* cow_op);
-
-    void* read_ahead_buffer_;
-    void* metadata_buffer_;
-    std::vector<const CowOperation*>::reverse_iterator read_ahead_iter_;
-    std::string cow_device_;
-    std::string backing_store_device_;
-    std::string misc_name_;
-
-    unique_fd cow_fd_;
-    unique_fd backing_store_fd_;
-
-    std::shared_ptr<Snapuserd> snapuserd_;
-
-    std::unordered_set<uint64_t> dest_blocks_;
-    std::unordered_set<uint64_t> source_blocks_;
-    bool overlap_;
-};
-
-class WorkerThread {
-  public:
-    WorkerThread(const std::string& cow_device, const std::string& backing_device,
-                 const std::string& control_device, const std::string& misc_name,
-                 std::shared_ptr<Snapuserd> snapuserd);
-    bool RunThread();
-
-  private:
-    // Initialization
-    void InitializeBufsink();
-    bool InitializeFds();
-    bool InitReader();
-    void CloseFds() {
-        ctrl_fd_ = {};
-        backing_store_fd_ = {};
-    }
-
-    // Functions interacting with dm-user
-    bool ReadDmUserHeader();
-    bool DmuserReadRequest();
-    bool DmuserWriteRequest();
-    bool ReadDmUserPayload(void* buffer, size_t size);
-    bool WriteDmUserPayload(size_t size, bool header_response);
-
-    bool ReadDiskExceptions(chunk_t chunk, size_t size);
-    bool ZerofillDiskExceptions(size_t read_size);
-    void ConstructKernelCowHeader();
-
-    // IO Path
-    bool ProcessIORequest();
-    int ReadData(sector_t sector, size_t size);
-    int ReadUnalignedSector(sector_t sector, size_t size,
-                            std::vector<std::pair<sector_t, const CowOperation*>>::iterator& it);
-
-    // Processing COW operations
-    bool ProcessCowOp(const CowOperation* cow_op);
-    bool ProcessReplaceOp(const CowOperation* cow_op);
-    // Handles Copy
-    bool ProcessCopyOp(const CowOperation* cow_op);
-    bool ProcessZeroOp();
-
-    bool ReadFromBaseDevice(const CowOperation* cow_op);
-    bool GetReadAheadPopulatedBuffer(const CowOperation* cow_op);
-
-    // Merge related functions
-    bool ProcessMergeComplete(chunk_t chunk, void* buffer);
-    loff_t GetMergeStartOffset(void* merged_buffer, void* unmerged_buffer,
-                               int* unmerged_exceptions);
-
-    int GetNumberOfMergedOps(void* merged_buffer, void* unmerged_buffer, loff_t offset,
-                             int unmerged_exceptions, bool* copy_op, bool* commit);
-
-    sector_t ChunkToSector(chunk_t chunk) { return chunk << CHUNK_SHIFT; }
-    chunk_t SectorToChunk(sector_t sector) { return sector >> CHUNK_SHIFT; }
-
-    std::unique_ptr<CowReader> reader_;
-    BufferSink bufsink_;
-
-    std::string cow_device_;
-    std::string backing_store_device_;
-    std::string control_device_;
-    std::string misc_name_;
-
-    unique_fd cow_fd_;
-    unique_fd backing_store_fd_;
-    unique_fd ctrl_fd_;
-
-    std::shared_ptr<Snapuserd> snapuserd_;
-    uint32_t exceptions_per_area_;
-};
-
-class Snapuserd : public std::enable_shared_from_this<Snapuserd> {
-  public:
-    Snapuserd(const std::string& misc_name, const std::string& cow_device,
-              const std::string& backing_device);
-    bool InitCowDevice();
-    bool Start();
-    const std::string& GetControlDevicePath() { return control_device_; }
-    const std::string& GetMiscName() { return misc_name_; }
-    uint64_t GetNumSectors() { return num_sectors_; }
-    bool IsAttached() const { return attached_; }
-    void AttachControlDevice() { attached_ = true; }
-
-    void CheckMergeCompletionStatus();
-    bool CommitMerge(int num_merge_ops);
-
-    void CloseFds() { cow_fd_ = {}; }
-    void FreeResources() {
-        worker_threads_.clear();
-        read_ahead_thread_ = nullptr;
-    }
-    size_t GetMetadataAreaSize() { return vec_.size(); }
-    void* GetExceptionBuffer(size_t i) { return vec_[i].get(); }
-
-    bool InitializeWorkers();
-    std::unique_ptr<CowReader> CloneReaderForWorker();
-    std::shared_ptr<Snapuserd> GetSharedPtr() { return shared_from_this(); }
-
-    std::vector<std::pair<sector_t, const CowOperation*>>& GetChunkVec() { return chunk_vec_; }
-    const std::vector<std::unique_ptr<uint8_t[]>>& GetMetadataVec() const { return vec_; }
-
-    static bool compare(std::pair<sector_t, const CowOperation*> p1,
-                        std::pair<sector_t, const CowOperation*> p2) {
-        return p1.first < p2.first;
-    }
-
-    void UnmapBufferRegion();
-    bool MmapMetadata();
-
-    // Read-ahead related functions
-    std::vector<const CowOperation*>& GetReadAheadOpsVec() { return read_ahead_ops_; }
-    std::unordered_map<uint64_t, void*>& GetReadAheadMap() { return read_ahead_buffer_map_; }
-    void* GetMappedAddr() { return mapped_addr_; }
-    bool IsReadAheadFeaturePresent() { return read_ahead_feature_; }
-    void PrepareReadAhead();
-    void StartReadAhead();
-    void MergeCompleted();
-    bool ReadAheadIOCompleted(bool sync);
-    void ReadAheadIOFailed();
-    bool WaitForMergeToComplete();
-    bool GetReadAheadPopulatedBuffer(uint64_t block, void* buffer);
-    bool ReconstructDataFromCow() { return populate_data_from_cow_; }
-    void ReconstructDataFromCowFinish() { populate_data_from_cow_ = false; }
-    bool WaitForReadAheadToStart();
-
-    uint64_t GetBufferMetadataOffset();
-    size_t GetBufferMetadataSize();
-    size_t GetBufferDataOffset();
-    size_t GetBufferDataSize();
-
-    // Final block to be merged in a given read-ahead buffer region
-    void SetFinalBlockMerged(uint64_t x) { final_block_merged_ = x; }
-    uint64_t GetFinalBlockMerged() { return final_block_merged_; }
-    // Total number of blocks to be merged in a given read-ahead buffer region
-    void SetTotalRaBlocksMerged(int x) { total_ra_blocks_merged_ = x; }
-    int GetTotalRaBlocksMerged() { return total_ra_blocks_merged_; }
-    void SetSocketPresent(bool socket) { is_socket_present_ = socket; }
-
-  private:
-    bool IsChunkIdMetadata(chunk_t chunk);
-    chunk_t GetNextAllocatableChunkId(chunk_t chunk_id);
-
-    bool GetRABuffer(std::unique_lock<std::mutex>* lock, uint64_t block, void* buffer);
-    bool ReadMetadata();
-    sector_t ChunkToSector(chunk_t chunk) { return chunk << CHUNK_SHIFT; }
-    chunk_t SectorToChunk(sector_t sector) { return sector >> CHUNK_SHIFT; }
-    bool IsBlockAligned(int read_size) { return ((read_size & (BLOCK_SZ - 1)) == 0); }
-    struct BufferState* GetBufferState();
-
-    void ReadBlocks(const std::string& partition_name, const std::string& dm_block_device);
-    void ReadBlocksToCache(const std::string& dm_block_device, const std::string& partition_name,
-                           off_t offset, size_t size);
-
-    std::string cow_device_;
-    std::string backing_store_device_;
-    std::string control_device_;
-    std::string misc_name_;
-
-    unique_fd cow_fd_;
-
-    uint32_t exceptions_per_area_;
-    uint64_t num_sectors_;
-
-    std::unique_ptr<CowReader> reader_;
-
-    // Vector of disk exception which is a
-    // mapping of old-chunk to new-chunk
-    std::vector<std::unique_ptr<uint8_t[]>> vec_;
-
-    // chunk_vec stores the pseudo mapping of sector
-    // to COW operations.
-    std::vector<std::pair<sector_t, const CowOperation*>> chunk_vec_;
-
-    std::mutex lock_;
-    std::condition_variable cv;
-
-    void* mapped_addr_;
-    size_t total_mapped_addr_length_;
-
-    std::vector<std::unique_ptr<WorkerThread>> worker_threads_;
-    // Read-ahead related
-    std::unordered_map<uint64_t, void*> read_ahead_buffer_map_;
-    std::vector<const CowOperation*> read_ahead_ops_;
-    bool populate_data_from_cow_ = false;
-    bool read_ahead_feature_;
-    uint64_t final_block_merged_;
-    int total_ra_blocks_merged_ = 0;
-    READ_AHEAD_IO_TRANSITION io_state_;
-    std::unique_ptr<ReadAheadThread> read_ahead_thread_;
-
-    bool merge_initiated_ = false;
-    bool attached_ = false;
-    bool is_socket_present_;
-};
-
-}  // namespace snapshot
-}  // namespace android
diff --git a/fs_mgr/libsnapshot/snapuserd/dm-snapshot-merge/snapuserd_readahead.cpp b/fs_mgr/libsnapshot/snapuserd/dm-snapshot-merge/snapuserd_readahead.cpp
deleted file mode 100644
index f1b9245..0000000
--- a/fs_mgr/libsnapshot/snapuserd/dm-snapshot-merge/snapuserd_readahead.cpp
+++ /dev/null
@@ -1,482 +0,0 @@
-/*
- * Copyright (C) 2021 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-#include "snapuserd.h"
-
-#include <csignal>
-#include <optional>
-#include <set>
-
-#include <snapuserd/snapuserd_client.h>
-
-namespace android {
-namespace snapshot {
-
-using namespace android;
-using namespace android::dm;
-using android::base::unique_fd;
-
-#define SNAP_LOG(level) LOG(level) << misc_name_ << ": "
-#define SNAP_PLOG(level) PLOG(level) << misc_name_ << ": "
-
-/*
- * Merging a copy operation involves the following flow:
- *
- * 1: dm-snapshot layer requests merge for a 4k block. dm-user sends the request
- *    to the daemon
- * 2: daemon reads the source block
- * 3: daemon copies the source data
- * 4: IO completion sent back to dm-user (a switch from user space to kernel)
- * 5: dm-snapshot merges the data to base device
- * 6: dm-snapshot sends the merge-completion IO to dm-user
- * 7: dm-user re-directs the merge completion IO to daemon (one more switch)
- * 8: daemon updates the COW file about the completed merge request (a write syscall) and followed
- * by a fysnc. 9: Send the IO completion back to dm-user
- *
- * The above sequence is a significant overhead especially when merging one 4k
- * block at a time.
- *
- * Read-ahead layer will optimize the above path by reading the data from base
- * device in the background so that merging thread can retrieve the data from
- * the read-ahead cache. Additionally, syncing of merged data is deferred to
- * read-ahead thread threadby the IO path is not bottlenecked.
- *
- * We create a scratch space of 2MB to store the read-ahead data in the COW
- * device.
- *
- *      +-----------------------+
- *      |     Header (fixed)    |
- *      +-----------------------+
- *      |    Scratch space      |  <-- 2MB
- *      +-----------------------+
- *
- *      Scratch space is as follows:
- *
- *      +-----------------------+
- *      |       Metadata        | <- 4k page
- *      +-----------------------+
- *      |       Metadata        | <- 4k page
- *      +-----------------------+
- *      |                       |
- *      |    Read-ahead data    |
- *      |                       |
- *      +-----------------------+
- *
- * State transitions and communication between read-ahead thread and worker
- * thread during merge:
- * =====================================================================
- *
- *   Worker Threads                                 Read-Ahead thread
- *   ------------------------------------------------------------------
- *
- *      |
- *      |
- *  --> -----------------READ_AHEAD_BEGIN------------->|
- *  |   |                                              | READ_AHEAD_IN_PROGRESS
- *  |  WAIT                                            |
- *  |   |                                              |
- *  |   |<-----------------IO_IN_PROGRESS---------------
- *  |   |                                              |
- *  |   | IO_IN_PRGRESS                               WAIT
- *  |   |                                              |
- *  |<--|                                              |
- *      |                                              |
- *      ------------------IO_TERMINATED--------------->|
- *                                                     END
- *
- *
- * ===================================================================
- *
- * Example:
- *
- * We have 6 copy operations to be executed in OTA and there is a overlap. Update-engine
- * will write to COW file as follows:
- *
- * Op-1: 20 -> 23
- * Op-2: 19 -> 22
- * Op-3: 18 -> 21
- * Op-4: 17 -> 20
- * Op-5: 16 -> 19
- * Op-6: 15 -> 18
- *
- * Read-ahead thread will read all the 6 source blocks and store the data in the
- * scratch space. Metadata will contain the destination block numbers. Thus,
- * scratch space will look something like this:
- *
- * +--------------+
- * | Block   23   |
- * | offset - 1   |
- * +--------------+
- * | Block   22   |
- * | offset - 2   |
- * +--------------+
- * | Block   21   |
- * | offset - 3   |
- * +--------------+
- *    ...
- *    ...
- * +--------------+
- * | Data-Block 20| <-- offset - 1
- * +--------------+
- * | Data-Block 19| <-- offset - 2
- * +--------------+
- * | Data-Block 18| <-- offset - 3
- * +--------------+
- *     ...
- *     ...
- *
- * ====================================================================
- * IO Path:
- *
- * Read-ahead will serve the data to worker threads during merge only
- * after metadata and data are persisted to the scratch space. Worker
- * threads during merge will always retrieve the data from cache; if the
- * cache is not populated, it will wait for the read-ahead thread to finish.
- * Furthermore, the number of operations merged will by synced to the header
- * only when all the blocks in the read-ahead cache are merged. In the above
- * case, when all 6 operations are merged, COW Header is updated with
- * num_merge_ops = 6.
- *
- * Merge resume after crash:
- *
- * Let's say we have a crash after 5 operations are merged. i.e. after
- * Op-5: 16->19 is completed but before the Op-6 is merged. Thus, COW Header
- * num_merge_ops will be 0 as the all the ops were not merged yet. During next
- * reboot, read-ahead thread will re-construct the data in-memory from the
- * scratch space; when merge resumes, Op-1 will be re-exectued. However,
- * data will be served from read-ahead cache safely even though, block 20
- * was over-written by Op-4.
- *
- */
-
-ReadAheadThread::ReadAheadThread(const std::string& cow_device, const std::string& backing_device,
-                                 const std::string& misc_name,
-                                 std::shared_ptr<Snapuserd> snapuserd) {
-    cow_device_ = cow_device;
-    backing_store_device_ = backing_device;
-    misc_name_ = misc_name;
-    snapuserd_ = snapuserd;
-}
-
-void ReadAheadThread::CheckOverlap(const CowOperation* cow_op) {
-    uint64_t source_block = cow_op->source();
-    if (dest_blocks_.count(cow_op->new_block) || source_blocks_.count(source_block)) {
-        overlap_ = true;
-    }
-
-    dest_blocks_.insert(source_block);
-    source_blocks_.insert(cow_op->new_block);
-}
-
-void ReadAheadThread::PrepareReadAhead(uint64_t* source_offset, int* pending_ops,
-                                       std::vector<uint64_t>& blocks) {
-    int num_ops = *pending_ops;
-    int nr_consecutive = 0;
-    CHECK_NE(source_offset, nullptr);
-
-    if (!RAIterDone() && num_ops) {
-        // Get the first block with offset
-        const CowOperation* cow_op = GetRAOpIter();
-        CHECK_NE(cow_op, nullptr);
-        *source_offset = cow_op->source();
-        if (cow_op->type() == kCowCopyOp) {
-            *source_offset *= BLOCK_SZ;
-        }
-        RAIterNext();
-        num_ops -= 1;
-        nr_consecutive = 1;
-        blocks.push_back(cow_op->new_block);
-
-        if (!overlap_) {
-            CheckOverlap(cow_op);
-        }
-
-        /*
-         * Find number of consecutive blocks working backwards.
-         */
-        while (!RAIterDone() && num_ops) {
-            const CowOperation* op = GetRAOpIter();
-            CHECK_NE(op, nullptr);
-            uint64_t next_offset = op->source();
-            if (op->type() == kCowCopyOp) {
-                next_offset *= BLOCK_SZ;
-            }
-            if (next_offset + nr_consecutive * BLOCK_SZ != *source_offset) {
-                break;
-            }
-            nr_consecutive += 1;
-            num_ops -= 1;
-            blocks.push_back(op->new_block);
-            RAIterNext();
-
-            if (!overlap_) {
-                CheckOverlap(op);
-            }
-        }
-    }
-}
-
-bool ReadAheadThread::ReconstructDataFromCow() {
-    std::unordered_map<uint64_t, void*>& read_ahead_buffer_map = snapuserd_->GetReadAheadMap();
-    read_ahead_buffer_map.clear();
-    loff_t metadata_offset = 0;
-    loff_t start_data_offset = snapuserd_->GetBufferDataOffset();
-    int num_ops = 0;
-    int total_blocks_merged = 0;
-
-    // This memcpy is important as metadata_buffer_ will be an unaligned address and will fault
-    // on 32-bit systems
-    std::unique_ptr<uint8_t[]> metadata_buffer =
-            std::make_unique<uint8_t[]>(snapuserd_->GetBufferMetadataSize());
-    memcpy(metadata_buffer.get(), metadata_buffer_, snapuserd_->GetBufferMetadataSize());
-
-    while (true) {
-        struct ScratchMetadata* bm = reinterpret_cast<struct ScratchMetadata*>(
-                (char*)metadata_buffer.get() + metadata_offset);
-
-        // Done reading metadata
-        if (bm->new_block == 0 && bm->file_offset == 0) {
-            break;
-        }
-
-        loff_t buffer_offset = bm->file_offset - start_data_offset;
-        void* bufptr = static_cast<void*>((char*)read_ahead_buffer_ + buffer_offset);
-        read_ahead_buffer_map[bm->new_block] = bufptr;
-        num_ops += 1;
-        total_blocks_merged += 1;
-
-        metadata_offset += sizeof(struct ScratchMetadata);
-    }
-
-    // We are done re-constructing the mapping; however, we need to make sure
-    // all the COW operations to-be merged are present in the re-constructed
-    // mapping.
-    while (!RAIterDone()) {
-        const CowOperation* op = GetRAOpIter();
-        if (read_ahead_buffer_map.find(op->new_block) != read_ahead_buffer_map.end()) {
-            num_ops -= 1;
-            snapuserd_->SetFinalBlockMerged(op->new_block);
-            RAIterNext();
-        } else {
-            // Verify that we have covered all the ops which were re-constructed
-            // from COW device - These are the ops which are being
-            // re-constructed after crash.
-            if (!(num_ops == 0)) {
-                SNAP_LOG(ERROR) << "ReconstructDataFromCow failed. Not all ops recoverd "
-                                << " Pending ops: " << num_ops;
-                snapuserd_->ReadAheadIOFailed();
-                return false;
-            }
-            break;
-        }
-    }
-
-    snapuserd_->SetTotalRaBlocksMerged(total_blocks_merged);
-
-    snapuserd_->ReconstructDataFromCowFinish();
-
-    if (!snapuserd_->ReadAheadIOCompleted(true)) {
-        SNAP_LOG(ERROR) << "ReadAheadIOCompleted failed...";
-        snapuserd_->ReadAheadIOFailed();
-        return false;
-    }
-
-    SNAP_LOG(INFO) << "ReconstructDataFromCow success";
-    return true;
-}
-
-bool ReadAheadThread::ReadAheadIOStart() {
-    // Check if the data has to be constructed from the COW file.
-    // This will be true only once during boot up after a crash
-    // during merge.
-    if (snapuserd_->ReconstructDataFromCow()) {
-        return ReconstructDataFromCow();
-    }
-
-    std::unordered_map<uint64_t, void*>& read_ahead_buffer_map = snapuserd_->GetReadAheadMap();
-    read_ahead_buffer_map.clear();
-
-    int num_ops = (snapuserd_->GetBufferDataSize()) / BLOCK_SZ;
-    loff_t metadata_offset = 0;
-
-    struct ScratchMetadata* bm =
-            reinterpret_cast<struct ScratchMetadata*>((char*)metadata_buffer_ + metadata_offset);
-
-    bm->new_block = 0;
-    bm->file_offset = 0;
-
-    std::vector<uint64_t> blocks;
-
-    loff_t buffer_offset = 0;
-    loff_t offset = 0;
-    loff_t file_offset = snapuserd_->GetBufferDataOffset();
-    int total_blocks_merged = 0;
-    overlap_ = false;
-    dest_blocks_.clear();
-    source_blocks_.clear();
-
-    while (true) {
-        uint64_t source_offset;
-        int linear_blocks;
-
-        PrepareReadAhead(&source_offset, &num_ops, blocks);
-        linear_blocks = blocks.size();
-        if (linear_blocks == 0) {
-            // No more blocks to read
-            SNAP_LOG(DEBUG) << " Read-ahead completed....";
-            break;
-        }
-
-        // Get the first block in the consecutive set of blocks
-        source_offset = source_offset - (linear_blocks - 1) * BLOCK_SZ;
-        size_t io_size = (linear_blocks * BLOCK_SZ);
-        num_ops -= linear_blocks;
-        total_blocks_merged += linear_blocks;
-
-        // Mark the block number as the one which will
-        // be the final block to be merged in this entire region.
-        // Read-ahead thread will get
-        // notified when this block is merged to make
-        // forward progress
-        snapuserd_->SetFinalBlockMerged(blocks.back());
-
-        while (linear_blocks) {
-            uint64_t new_block = blocks.back();
-            blocks.pop_back();
-            // Assign the mapping
-            void* bufptr = static_cast<void*>((char*)read_ahead_buffer_ + offset);
-            read_ahead_buffer_map[new_block] = bufptr;
-            offset += BLOCK_SZ;
-
-            bm = reinterpret_cast<struct ScratchMetadata*>((char*)metadata_buffer_ +
-                                                           metadata_offset);
-            bm->new_block = new_block;
-            bm->file_offset = file_offset;
-
-            metadata_offset += sizeof(struct ScratchMetadata);
-            file_offset += BLOCK_SZ;
-
-            linear_blocks -= 1;
-        }
-
-        // Read from the base device consecutive set of blocks in one shot
-        if (!android::base::ReadFullyAtOffset(backing_store_fd_,
-                                              (char*)read_ahead_buffer_ + buffer_offset, io_size,
-                                              source_offset)) {
-            SNAP_PLOG(ERROR) << "Ordered-op failed. Read from backing store: "
-                             << backing_store_device_ << "at block :" << source_offset / BLOCK_SZ
-                             << " offset :" << source_offset % BLOCK_SZ
-                             << " buffer_offset : " << buffer_offset << " io_size : " << io_size
-                             << " buf-addr : " << read_ahead_buffer_;
-
-            snapuserd_->ReadAheadIOFailed();
-            return false;
-        }
-
-        // This is important - explicitly set the contents to zero. This is used
-        // when re-constructing the data after crash. This indicates end of
-        // reading metadata contents when re-constructing the data
-        bm = reinterpret_cast<struct ScratchMetadata*>((char*)metadata_buffer_ + metadata_offset);
-        bm->new_block = 0;
-        bm->file_offset = 0;
-
-        buffer_offset += io_size;
-    }
-
-    snapuserd_->SetTotalRaBlocksMerged(total_blocks_merged);
-
-    // Flush the data only if we have a overlapping blocks in the region
-    if (!snapuserd_->ReadAheadIOCompleted(overlap_)) {
-        SNAP_LOG(ERROR) << "ReadAheadIOCompleted failed...";
-        snapuserd_->ReadAheadIOFailed();
-        return false;
-    }
-
-    return true;
-}
-
-bool ReadAheadThread::RunThread() {
-    if (!InitializeFds()) {
-        return false;
-    }
-
-    InitializeRAIter();
-    InitializeBuffer();
-
-    while (!RAIterDone()) {
-        if (!ReadAheadIOStart()) {
-            return false;
-        }
-
-        bool status = snapuserd_->WaitForMergeToComplete();
-
-        if (status && !snapuserd_->CommitMerge(snapuserd_->GetTotalRaBlocksMerged())) {
-            return false;
-        }
-
-        if (!status) break;
-    }
-
-    CloseFds();
-    SNAP_LOG(INFO) << " ReadAhead thread terminating....";
-    return true;
-}
-
-// Initialization
-bool ReadAheadThread::InitializeFds() {
-    backing_store_fd_.reset(open(backing_store_device_.c_str(), O_RDONLY));
-    if (backing_store_fd_ < 0) {
-        SNAP_PLOG(ERROR) << "Open Failed: " << backing_store_device_;
-        return false;
-    }
-
-    cow_fd_.reset(open(cow_device_.c_str(), O_RDWR));
-    if (cow_fd_ < 0) {
-        SNAP_PLOG(ERROR) << "Open Failed: " << cow_device_;
-        return false;
-    }
-
-    return true;
-}
-
-void ReadAheadThread::InitializeRAIter() {
-    std::vector<const CowOperation*>& read_ahead_ops = snapuserd_->GetReadAheadOpsVec();
-    read_ahead_iter_ = read_ahead_ops.rbegin();
-}
-
-bool ReadAheadThread::RAIterDone() {
-    std::vector<const CowOperation*>& read_ahead_ops = snapuserd_->GetReadAheadOpsVec();
-    return read_ahead_iter_ == read_ahead_ops.rend();
-}
-
-void ReadAheadThread::RAIterNext() {
-    read_ahead_iter_++;
-}
-
-const CowOperation* ReadAheadThread::GetRAOpIter() {
-    return *read_ahead_iter_;
-}
-
-void ReadAheadThread::InitializeBuffer() {
-    void* mapped_addr = snapuserd_->GetMappedAddr();
-    // Map the scratch space region into memory
-    metadata_buffer_ =
-            static_cast<void*>((char*)mapped_addr + snapuserd_->GetBufferMetadataOffset());
-    read_ahead_buffer_ = static_cast<void*>((char*)mapped_addr + snapuserd_->GetBufferDataOffset());
-}
-
-}  // namespace snapshot
-}  // namespace android
diff --git a/fs_mgr/libsnapshot/snapuserd/dm-snapshot-merge/snapuserd_server.cpp b/fs_mgr/libsnapshot/snapuserd/dm-snapshot-merge/snapuserd_server.cpp
deleted file mode 100644
index 577b09d..0000000
--- a/fs_mgr/libsnapshot/snapuserd/dm-snapshot-merge/snapuserd_server.cpp
+++ /dev/null
@@ -1,559 +0,0 @@
-/*
- * Copyright (C) 2020 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-#include <arpa/inet.h>
-#include <cutils/sockets.h>
-#include <errno.h>
-#include <netinet/in.h>
-#include <stdint.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <sys/socket.h>
-#include <sys/types.h>
-#include <unistd.h>
-
-#include <android-base/cmsg.h>
-#include <android-base/logging.h>
-#include <android-base/properties.h>
-#include <android-base/scopeguard.h>
-#include <fs_mgr/file_wait.h>
-#include <snapuserd/snapuserd_client.h>
-
-#include "snapuserd_server.h"
-
-#define _REALLY_INCLUDE_SYS__SYSTEM_PROPERTIES_H_
-#include <sys/_system_properties.h>
-
-namespace android {
-namespace snapshot {
-
-using namespace std::string_literals;
-
-using android::base::borrowed_fd;
-using android::base::unique_fd;
-
-DaemonOperations SnapuserdServer::Resolveop(std::string& input) {
-    if (input == "init") return DaemonOperations::INIT;
-    if (input == "start") return DaemonOperations::START;
-    if (input == "stop") return DaemonOperations::STOP;
-    if (input == "query") return DaemonOperations::QUERY;
-    if (input == "delete") return DaemonOperations::DELETE;
-    if (input == "detach") return DaemonOperations::DETACH;
-    if (input == "supports") return DaemonOperations::SUPPORTS;
-
-    return DaemonOperations::INVALID;
-}
-
-SnapuserdServer::~SnapuserdServer() {
-    // Close any client sockets that were added via AcceptClient().
-    for (size_t i = 1; i < watched_fds_.size(); i++) {
-        close(watched_fds_[i].fd);
-    }
-}
-
-std::string SnapuserdServer::GetDaemonStatus() {
-    std::string msg = "";
-
-    if (IsTerminating())
-        msg = "passive";
-    else
-        msg = "active";
-
-    return msg;
-}
-
-void SnapuserdServer::Parsemsg(std::string const& msg, const char delim,
-                               std::vector<std::string>& out) {
-    std::stringstream ss(msg);
-    std::string s;
-
-    while (std::getline(ss, s, delim)) {
-        out.push_back(s);
-    }
-}
-
-void SnapuserdServer::ShutdownThreads() {
-    StopThreads();
-    JoinAllThreads();
-}
-
-DmUserHandler::DmUserHandler(std::shared_ptr<Snapuserd> snapuserd)
-    : snapuserd_(snapuserd), misc_name_(snapuserd_->GetMiscName()) {}
-
-bool SnapuserdServer::Sendmsg(android::base::borrowed_fd fd, const std::string& msg) {
-    ssize_t ret = TEMP_FAILURE_RETRY(send(fd.get(), msg.data(), msg.size(), MSG_NOSIGNAL));
-    if (ret < 0) {
-        PLOG(ERROR) << "Snapuserd:server: send() failed";
-        return false;
-    }
-
-    if (ret < msg.size()) {
-        LOG(ERROR) << "Partial send; expected " << msg.size() << " bytes, sent " << ret;
-        return false;
-    }
-    return true;
-}
-
-bool SnapuserdServer::Recv(android::base::borrowed_fd fd, std::string* data) {
-    char msg[MAX_PACKET_SIZE];
-    ssize_t rv = TEMP_FAILURE_RETRY(recv(fd.get(), msg, sizeof(msg), 0));
-    if (rv < 0) {
-        PLOG(ERROR) << "recv failed";
-        return false;
-    }
-    *data = std::string(msg, rv);
-    return true;
-}
-
-bool SnapuserdServer::Receivemsg(android::base::borrowed_fd fd, const std::string& str) {
-    const char delim = ',';
-
-    std::vector<std::string> out;
-    Parsemsg(str, delim, out);
-    DaemonOperations op = Resolveop(out[0]);
-
-    switch (op) {
-        case DaemonOperations::INIT: {
-            // Message format:
-            // init,<misc_name>,<cow_device_path>,<backing_device>
-            //
-            // Reads the metadata and send the number of sectors
-            if (out.size() != 4) {
-                LOG(ERROR) << "Malformed init message, " << out.size() << " parts";
-                return Sendmsg(fd, "fail");
-            }
-
-            auto handler = AddHandler(out[1], out[2], out[3]);
-            if (!handler) {
-                return Sendmsg(fd, "fail");
-            }
-
-            auto retval = "success," + std::to_string(handler->snapuserd()->GetNumSectors());
-            return Sendmsg(fd, retval);
-        }
-        case DaemonOperations::START: {
-            // Message format:
-            // start,<misc_name>
-            //
-            // Start the new thread which binds to dm-user misc device
-            if (out.size() != 2) {
-                LOG(ERROR) << "Malformed start message, " << out.size() << " parts";
-                return Sendmsg(fd, "fail");
-            }
-
-            std::lock_guard<std::mutex> lock(lock_);
-            auto iter = FindHandler(&lock, out[1]);
-            if (iter == dm_users_.end()) {
-                LOG(ERROR) << "Could not find handler: " << out[1];
-                return Sendmsg(fd, "fail");
-            }
-            if (!(*iter)->snapuserd() || (*iter)->snapuserd()->IsAttached()) {
-                LOG(ERROR) << "Tried to re-attach control device: " << out[1];
-                return Sendmsg(fd, "fail");
-            }
-            if (!StartHandler(*iter)) {
-                return Sendmsg(fd, "fail");
-            }
-            return Sendmsg(fd, "success");
-        }
-        case DaemonOperations::STOP: {
-            // Message format: stop
-            //
-            // Stop all the threads gracefully and then shutdown the
-            // main thread
-            SetTerminating();
-            ShutdownThreads();
-            return true;
-        }
-        case DaemonOperations::QUERY: {
-            // Message format: query
-            //
-            // As part of transition, Second stage daemon will be
-            // created before terminating the first stage daemon. Hence,
-            // for a brief period client may have to distiguish between
-            // first stage daemon and second stage daemon.
-            //
-            // Second stage daemon is marked as active and hence will
-            // be ready to receive control message.
-            return Sendmsg(fd, GetDaemonStatus());
-        }
-        case DaemonOperations::DELETE: {
-            // Message format:
-            // delete,<misc_name>
-            if (out.size() != 2) {
-                LOG(ERROR) << "Malformed delete message, " << out.size() << " parts";
-                return Sendmsg(fd, "fail");
-            }
-            if (!RemoveAndJoinHandler(out[1])) {
-                return Sendmsg(fd, "fail");
-            }
-            return Sendmsg(fd, "success");
-        }
-        case DaemonOperations::DETACH: {
-            terminating_ = true;
-            return true;
-        }
-        case DaemonOperations::SUPPORTS: {
-            if (out.size() != 2) {
-                LOG(ERROR) << "Malformed supports message, " << out.size() << " parts";
-                return Sendmsg(fd, "fail");
-            }
-            if (out[1] == "second_stage_socket_handoff") {
-                return Sendmsg(fd, "success");
-            }
-            return Sendmsg(fd, "fail");
-        }
-        default: {
-            LOG(ERROR) << "Received unknown message type from client";
-            Sendmsg(fd, "fail");
-            return false;
-        }
-    }
-}
-
-void SnapuserdServer::RunThread(std::shared_ptr<DmUserHandler> handler) {
-    LOG(INFO) << "Entering thread for handler: " << handler->misc_name();
-
-    handler->snapuserd()->SetSocketPresent(is_socket_present_);
-    if (!handler->snapuserd()->Start()) {
-        LOG(ERROR) << " Failed to launch all worker threads";
-    }
-
-    handler->snapuserd()->CloseFds();
-    handler->snapuserd()->CheckMergeCompletionStatus();
-    handler->snapuserd()->UnmapBufferRegion();
-
-    auto misc_name = handler->misc_name();
-    LOG(INFO) << "Handler thread about to exit: " << misc_name;
-
-    {
-        std::lock_guard<std::mutex> lock(lock_);
-        auto iter = FindHandler(&lock, handler->misc_name());
-        if (iter == dm_users_.end()) {
-            // RemoveAndJoinHandler() already removed us from the list, and is
-            // now waiting on a join(), so just return. Additionally, release
-            // all the resources held by snapuserd object which are shared
-            // by worker threads. This should be done when the last reference
-            // of "handler" is released; but we will explicitly release here
-            // to make sure snapuserd object is freed as it is the biggest
-            // consumer of memory in the daemon.
-            handler->FreeResources();
-            LOG(INFO) << "Exiting handler thread to allow for join: " << misc_name;
-            return;
-        }
-
-        LOG(INFO) << "Exiting handler thread and freeing resources: " << misc_name;
-
-        if (handler->snapuserd()->IsAttached()) {
-            handler->thread().detach();
-        }
-
-        // Important: free resources within the lock. This ensures that if
-        // WaitForDelete() is called, the handler is either in the list, or
-        // it's not and its resources are guaranteed to be freed.
-        handler->FreeResources();
-    }
-}
-
-bool SnapuserdServer::Start(const std::string& socketname) {
-    bool start_listening = true;
-
-    sockfd_.reset(android_get_control_socket(socketname.c_str()));
-    if (sockfd_ < 0) {
-        sockfd_.reset(socket_local_server(socketname.c_str(), ANDROID_SOCKET_NAMESPACE_RESERVED,
-                                          SOCK_STREAM));
-        if (sockfd_ < 0) {
-            PLOG(ERROR) << "Failed to create server socket " << socketname;
-            return false;
-        }
-        start_listening = false;
-    }
-    return StartWithSocket(start_listening);
-}
-
-bool SnapuserdServer::StartWithSocket(bool start_listening) {
-    if (start_listening && listen(sockfd_.get(), 4) < 0) {
-        PLOG(ERROR) << "listen socket failed";
-        return false;
-    }
-
-    AddWatchedFd(sockfd_, POLLIN);
-    is_socket_present_ = true;
-
-    // If started in first-stage init, the property service won't be online.
-    if (access("/dev/socket/property_service", F_OK) == 0) {
-        if (!android::base::SetProperty("snapuserd.ready", "true")) {
-            LOG(ERROR) << "Failed to set snapuserd.ready property";
-            return false;
-        }
-    }
-
-    LOG(DEBUG) << "Snapuserd server now accepting connections";
-    return true;
-}
-
-bool SnapuserdServer::Run() {
-    LOG(INFO) << "Now listening on snapuserd socket";
-
-    while (!IsTerminating()) {
-        int rv = TEMP_FAILURE_RETRY(poll(watched_fds_.data(), watched_fds_.size(), -1));
-        if (rv < 0) {
-            PLOG(ERROR) << "poll failed";
-            return false;
-        }
-        if (!rv) {
-            continue;
-        }
-
-        if (watched_fds_[0].revents) {
-            AcceptClient();
-        }
-
-        auto iter = watched_fds_.begin() + 1;
-        while (iter != watched_fds_.end()) {
-            if (iter->revents && !HandleClient(iter->fd, iter->revents)) {
-                close(iter->fd);
-                iter = watched_fds_.erase(iter);
-            } else {
-                iter++;
-            }
-        }
-    }
-
-    JoinAllThreads();
-    return true;
-}
-
-void SnapuserdServer::JoinAllThreads() {
-    // Acquire the thread list within the lock.
-    std::vector<std::shared_ptr<DmUserHandler>> dm_users;
-    {
-        std::lock_guard<std::mutex> guard(lock_);
-        dm_users = std::move(dm_users_);
-    }
-
-    for (auto& client : dm_users) {
-        auto& th = client->thread();
-
-        if (th.joinable()) th.join();
-    }
-}
-
-void SnapuserdServer::AddWatchedFd(android::base::borrowed_fd fd, int events) {
-    struct pollfd p = {};
-    p.fd = fd.get();
-    p.events = events;
-    watched_fds_.emplace_back(std::move(p));
-}
-
-void SnapuserdServer::AcceptClient() {
-    int fd = TEMP_FAILURE_RETRY(accept4(sockfd_.get(), nullptr, nullptr, SOCK_CLOEXEC));
-    if (fd < 0) {
-        PLOG(ERROR) << "accept4 failed";
-        return;
-    }
-
-    AddWatchedFd(fd, POLLIN);
-}
-
-bool SnapuserdServer::HandleClient(android::base::borrowed_fd fd, int revents) {
-    if (revents & POLLHUP) {
-        LOG(DEBUG) << "Snapuserd client disconnected";
-        return false;
-    }
-
-    std::string str;
-    if (!Recv(fd, &str)) {
-        return false;
-    }
-    if (!Receivemsg(fd, str)) {
-        LOG(ERROR) << "Encountered error handling client message, revents: " << revents;
-        return false;
-    }
-    return true;
-}
-
-void SnapuserdServer::Interrupt() {
-    // Force close the socket so poll() fails.
-    sockfd_ = {};
-    SetTerminating();
-}
-
-std::shared_ptr<DmUserHandler> SnapuserdServer::AddHandler(const std::string& misc_name,
-                                                           const std::string& cow_device_path,
-                                                           const std::string& backing_device) {
-    auto snapuserd = std::make_shared<Snapuserd>(misc_name, cow_device_path, backing_device);
-    if (!snapuserd->InitCowDevice()) {
-        LOG(ERROR) << "Failed to initialize Snapuserd";
-        return nullptr;
-    }
-
-    if (!snapuserd->InitializeWorkers()) {
-        LOG(ERROR) << "Failed to initialize workers";
-        return nullptr;
-    }
-
-    auto handler = std::make_shared<DmUserHandler>(snapuserd);
-    {
-        std::lock_guard<std::mutex> lock(lock_);
-        if (FindHandler(&lock, misc_name) != dm_users_.end()) {
-            LOG(ERROR) << "Handler already exists: " << misc_name;
-            return nullptr;
-        }
-        dm_users_.push_back(handler);
-    }
-    return handler;
-}
-
-bool SnapuserdServer::StartHandler(const std::shared_ptr<DmUserHandler>& handler) {
-    if (handler->snapuserd()->IsAttached()) {
-        LOG(ERROR) << "Handler already attached";
-        return false;
-    }
-
-    handler->snapuserd()->AttachControlDevice();
-
-    handler->thread() = std::thread(std::bind(&SnapuserdServer::RunThread, this, handler));
-    return true;
-}
-
-auto SnapuserdServer::FindHandler(std::lock_guard<std::mutex>* proof_of_lock,
-                                  const std::string& misc_name) -> HandlerList::iterator {
-    CHECK(proof_of_lock);
-
-    for (auto iter = dm_users_.begin(); iter != dm_users_.end(); iter++) {
-        if ((*iter)->misc_name() == misc_name) {
-            return iter;
-        }
-    }
-    return dm_users_.end();
-}
-
-bool SnapuserdServer::RemoveAndJoinHandler(const std::string& misc_name) {
-    std::shared_ptr<DmUserHandler> handler;
-    {
-        std::lock_guard<std::mutex> lock(lock_);
-
-        auto iter = FindHandler(&lock, misc_name);
-        if (iter == dm_users_.end()) {
-            // Client already deleted.
-            return true;
-        }
-        handler = std::move(*iter);
-        dm_users_.erase(iter);
-    }
-
-    auto& th = handler->thread();
-    if (th.joinable()) {
-        th.join();
-    }
-    return true;
-}
-
-bool SnapuserdServer::WaitForSocket() {
-    auto scope_guard = android::base::make_scope_guard([this]() -> void { JoinAllThreads(); });
-
-    auto socket_path = ANDROID_SOCKET_DIR "/"s + kSnapuserdSocketProxy;
-
-    if (!android::fs_mgr::WaitForFile(socket_path, std::chrono::milliseconds::max())) {
-        LOG(ERROR)
-                << "Failed to wait for proxy socket, second-stage snapuserd will fail to connect";
-        return false;
-    }
-
-    // We must re-initialize property service access, since we launched before
-    // second-stage init.
-    __system_properties_init();
-
-    if (!android::base::WaitForProperty("snapuserd.proxy_ready", "true")) {
-        LOG(ERROR)
-                << "Failed to wait for proxy property, second-stage snapuserd will fail to connect";
-        return false;
-    }
-
-    unique_fd fd(socket_local_client(kSnapuserdSocketProxy, ANDROID_SOCKET_NAMESPACE_RESERVED,
-                                     SOCK_SEQPACKET));
-    if (fd < 0) {
-        PLOG(ERROR) << "Failed to connect to socket proxy";
-        return false;
-    }
-
-    char code[1];
-    std::vector<unique_fd> fds;
-    ssize_t rv = android::base::ReceiveFileDescriptorVector(fd, code, sizeof(code), 1, &fds);
-    if (rv < 0) {
-        PLOG(ERROR) << "Failed to receive server socket over proxy";
-        return false;
-    }
-    if (fds.empty()) {
-        LOG(ERROR) << "Expected at least one file descriptor from proxy";
-        return false;
-    }
-
-    // We don't care if the ACK is received.
-    code[0] = 'a';
-    if (TEMP_FAILURE_RETRY(send(fd, code, sizeof(code), MSG_NOSIGNAL)) < 0) {
-        PLOG(ERROR) << "Failed to send ACK to proxy";
-        return false;
-    }
-
-    sockfd_ = std::move(fds[0]);
-    if (!StartWithSocket(true)) {
-        return false;
-    }
-    return Run();
-}
-
-bool SnapuserdServer::RunForSocketHandoff() {
-    unique_fd proxy_fd(android_get_control_socket(kSnapuserdSocketProxy));
-    if (proxy_fd < 0) {
-        PLOG(FATAL) << "Proxy could not get android control socket " << kSnapuserdSocketProxy;
-    }
-    borrowed_fd server_fd(android_get_control_socket(kSnapuserdSocket));
-    if (server_fd < 0) {
-        PLOG(FATAL) << "Proxy could not get android control socket " << kSnapuserdSocket;
-    }
-
-    if (listen(proxy_fd.get(), 4) < 0) {
-        PLOG(FATAL) << "Proxy listen socket failed";
-    }
-
-    if (!android::base::SetProperty("snapuserd.proxy_ready", "true")) {
-        LOG(FATAL) << "Proxy failed to set ready property";
-    }
-
-    unique_fd client_fd(
-            TEMP_FAILURE_RETRY(accept4(proxy_fd.get(), nullptr, nullptr, SOCK_CLOEXEC)));
-    if (client_fd < 0) {
-        PLOG(FATAL) << "Proxy accept failed";
-    }
-
-    char code[1] = {'a'};
-    std::vector<int> fds = {server_fd.get()};
-    ssize_t rv = android::base::SendFileDescriptorVector(client_fd, code, sizeof(code), fds);
-    if (rv < 0) {
-        PLOG(FATAL) << "Proxy could not send file descriptor to snapuserd";
-    }
-    // Wait for an ACK - results don't matter, we just don't want to risk closing
-    // the proxy socket too early.
-    if (recv(client_fd, code, sizeof(code), 0) < 0) {
-        PLOG(FATAL) << "Proxy could not receive terminating code from snapuserd";
-    }
-    return true;
-}
-
-}  // namespace snapshot
-}  // namespace android
diff --git a/fs_mgr/libsnapshot/snapuserd/dm-snapshot-merge/snapuserd_server.h b/fs_mgr/libsnapshot/snapuserd/dm-snapshot-merge/snapuserd_server.h
deleted file mode 100644
index 3b6ff15..0000000
--- a/fs_mgr/libsnapshot/snapuserd/dm-snapshot-merge/snapuserd_server.h
+++ /dev/null
@@ -1,149 +0,0 @@
-// Copyright (C) 2020 The Android Open Source Project
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//      http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-#pragma once
-
-#include <poll.h>
-
-#include <cstdio>
-#include <cstring>
-#include <functional>
-#include <future>
-#include <iostream>
-#include <mutex>
-#include <sstream>
-#include <string>
-#include <thread>
-#include <vector>
-
-#include <android-base/unique_fd.h>
-#include "snapuserd.h"
-
-namespace android {
-namespace snapshot {
-
-static constexpr uint32_t MAX_PACKET_SIZE = 512;
-
-enum class DaemonOperations {
-    INIT,
-    START,
-    QUERY,
-    STOP,
-    DELETE,
-    DETACH,
-    SUPPORTS,
-    INVALID,
-};
-
-class DmUserHandler {
-  public:
-    explicit DmUserHandler(std::shared_ptr<Snapuserd> snapuserd);
-
-    void FreeResources() {
-        // Each worker thread holds a reference to snapuserd.
-        // Clear them so that all the resources
-        // held by snapuserd is released
-        if (snapuserd_) {
-            snapuserd_->FreeResources();
-            snapuserd_ = nullptr;
-        }
-    }
-    const std::shared_ptr<Snapuserd>& snapuserd() const { return snapuserd_; }
-    std::thread& thread() { return thread_; }
-
-    const std::string& misc_name() const { return misc_name_; }
-
-  private:
-    std::thread thread_;
-    std::shared_ptr<Snapuserd> snapuserd_;
-    std::string misc_name_;
-};
-
-class Stoppable {
-    std::promise<void> exitSignal_;
-    std::future<void> futureObj_;
-
-  public:
-    Stoppable() : futureObj_(exitSignal_.get_future()) {}
-
-    virtual ~Stoppable() {}
-
-    bool StopRequested() {
-        // checks if value in future object is available
-        if (futureObj_.wait_for(std::chrono::milliseconds(0)) == std::future_status::timeout) {
-            return false;
-        }
-        return true;
-    }
-    // Request the thread to stop by setting value in promise object
-    void StopThreads() { exitSignal_.set_value(); }
-};
-
-class SnapuserdServer : public Stoppable {
-  private:
-    android::base::unique_fd sockfd_;
-    bool terminating_;
-    volatile bool received_socket_signal_ = false;
-    std::vector<struct pollfd> watched_fds_;
-    bool is_socket_present_ = false;
-
-    std::mutex lock_;
-
-    using HandlerList = std::vector<std::shared_ptr<DmUserHandler>>;
-    HandlerList dm_users_;
-
-    void AddWatchedFd(android::base::borrowed_fd fd, int events);
-    void AcceptClient();
-    bool HandleClient(android::base::borrowed_fd fd, int revents);
-    bool Recv(android::base::borrowed_fd fd, std::string* data);
-    bool Sendmsg(android::base::borrowed_fd fd, const std::string& msg);
-    bool Receivemsg(android::base::borrowed_fd fd, const std::string& str);
-
-    void ShutdownThreads();
-    bool RemoveAndJoinHandler(const std::string& control_device);
-    DaemonOperations Resolveop(std::string& input);
-    std::string GetDaemonStatus();
-    void Parsemsg(std::string const& msg, const char delim, std::vector<std::string>& out);
-
-    bool IsTerminating() { return terminating_; }
-
-    void RunThread(std::shared_ptr<DmUserHandler> handler);
-    void JoinAllThreads();
-    bool StartWithSocket(bool start_listening);
-
-    // Find a DmUserHandler within a lock.
-    HandlerList::iterator FindHandler(std::lock_guard<std::mutex>* proof_of_lock,
-                                      const std::string& misc_name);
-
-  public:
-    SnapuserdServer() { terminating_ = false; }
-    ~SnapuserdServer();
-
-    bool Start(const std::string& socketname);
-    bool Run();
-    void Interrupt();
-    bool RunForSocketHandoff();
-    bool WaitForSocket();
-
-    std::shared_ptr<DmUserHandler> AddHandler(const std::string& misc_name,
-                                              const std::string& cow_device_path,
-                                              const std::string& backing_device);
-    bool StartHandler(const std::shared_ptr<DmUserHandler>& handler);
-
-    void SetTerminating() { terminating_ = true; }
-    void ReceivedSocketSignal() { received_socket_signal_ = true; }
-};
-
-}  // namespace snapshot
-}  // namespace android
diff --git a/fs_mgr/libsnapshot/snapuserd/dm-snapshot-merge/snapuserd_worker.cpp b/fs_mgr/libsnapshot/snapuserd/dm-snapshot-merge/snapuserd_worker.cpp
deleted file mode 100644
index 1f5d568..0000000
--- a/fs_mgr/libsnapshot/snapuserd/dm-snapshot-merge/snapuserd_worker.cpp
+++ /dev/null
@@ -1,869 +0,0 @@
-/*
- * Copyright (C) 2020 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-#include "snapuserd.h"
-
-#include <csignal>
-#include <optional>
-#include <set>
-
-#include <snapuserd/snapuserd_client.h>
-
-namespace android {
-namespace snapshot {
-
-using namespace android;
-using namespace android::dm;
-using android::base::unique_fd;
-
-#define SNAP_LOG(level) LOG(level) << misc_name_ << ": "
-#define SNAP_PLOG(level) PLOG(level) << misc_name_ << ": "
-
-WorkerThread::WorkerThread(const std::string& cow_device, const std::string& backing_device,
-                           const std::string& control_device, const std::string& misc_name,
-                           std::shared_ptr<Snapuserd> snapuserd) {
-    cow_device_ = cow_device;
-    backing_store_device_ = backing_device;
-    control_device_ = control_device;
-    misc_name_ = misc_name;
-    snapuserd_ = snapuserd;
-    exceptions_per_area_ = (CHUNK_SIZE << SECTOR_SHIFT) / sizeof(struct disk_exception);
-}
-
-bool WorkerThread::InitializeFds() {
-    backing_store_fd_.reset(open(backing_store_device_.c_str(), O_RDONLY));
-    if (backing_store_fd_ < 0) {
-        SNAP_PLOG(ERROR) << "Open Failed: " << backing_store_device_;
-        return false;
-    }
-
-    cow_fd_.reset(open(cow_device_.c_str(), O_RDWR));
-    if (cow_fd_ < 0) {
-        SNAP_PLOG(ERROR) << "Open Failed: " << cow_device_;
-        return false;
-    }
-
-    ctrl_fd_.reset(open(control_device_.c_str(), O_RDWR));
-    if (ctrl_fd_ < 0) {
-        SNAP_PLOG(ERROR) << "Unable to open " << control_device_;
-        return false;
-    }
-
-    return true;
-}
-
-bool WorkerThread::InitReader() {
-    reader_ = snapuserd_->CloneReaderForWorker();
-
-    if (!reader_->InitForMerge(std::move(cow_fd_))) {
-        return false;
-    }
-    return true;
-}
-
-// Construct kernel COW header in memory
-// This header will be in sector 0. The IO
-// request will always be 4k. After constructing
-// the header, zero out the remaining block.
-void WorkerThread::ConstructKernelCowHeader() {
-    void* buffer = bufsink_.GetPayloadBuffer(BLOCK_SZ);
-
-    memset(buffer, 0, BLOCK_SZ);
-
-    struct disk_header* dh = reinterpret_cast<struct disk_header*>(buffer);
-
-    dh->magic = SNAP_MAGIC;
-    dh->valid = SNAPSHOT_VALID;
-    dh->version = SNAPSHOT_DISK_VERSION;
-    dh->chunk_size = CHUNK_SIZE;
-}
-
-// Start the replace operation. This will read the
-// internal COW format and if the block is compressed,
-// it will be de-compressed.
-bool WorkerThread::ProcessReplaceOp(const CowOperation* cow_op) {
-    void* buffer = bufsink_.GetPayloadBuffer(BLOCK_SZ);
-    if (!buffer) {
-        SNAP_LOG(ERROR) << "No space in buffer sink";
-        return false;
-    }
-    ssize_t rv = reader_->ReadData(cow_op, buffer, BLOCK_SZ);
-    if (rv != BLOCK_SZ) {
-        SNAP_LOG(ERROR) << "ProcessReplaceOp failed for block " << cow_op->new_block
-                        << ", return = " << rv << ", COW operation = " << *cow_op;
-        return false;
-    }
-    return true;
-}
-
-bool WorkerThread::ReadFromBaseDevice(const CowOperation* cow_op) {
-    void* buffer = bufsink_.GetPayloadBuffer(BLOCK_SZ);
-    if (buffer == nullptr) {
-        SNAP_LOG(ERROR) << "ReadFromBaseDevice: Failed to get payload buffer";
-        return false;
-    }
-    uint64_t offset;
-    if (!reader_->GetSourceOffset(cow_op, &offset)) {
-        SNAP_LOG(ERROR) << "ReadFromBaseDevice: Failed to get source offset";
-        return false;
-    }
-    SNAP_LOG(DEBUG) << " ReadFromBaseDevice...: new-block: " << cow_op->new_block
-                    << " Source: " << offset;
-    if (!android::base::ReadFullyAtOffset(backing_store_fd_, buffer, BLOCK_SZ, offset)) {
-        SNAP_PLOG(ERROR) << "Copy op failed. Read from backing store: " << backing_store_device_
-                         << "at block :" << offset / BLOCK_SZ << " offset:" << offset % BLOCK_SZ;
-        return false;
-    }
-
-    return true;
-}
-
-bool WorkerThread::GetReadAheadPopulatedBuffer(const CowOperation* cow_op) {
-    void* buffer = bufsink_.GetPayloadBuffer(BLOCK_SZ);
-    if (buffer == nullptr) {
-        SNAP_LOG(ERROR) << "GetReadAheadPopulatedBuffer: Failed to get payload buffer";
-        return false;
-    }
-
-    if (!snapuserd_->GetReadAheadPopulatedBuffer(cow_op->new_block, buffer)) {
-        return false;
-    }
-
-    return true;
-}
-
-// Start the copy operation. This will read the backing
-// block device which is represented by cow_op->source.
-bool WorkerThread::ProcessCopyOp(const CowOperation* cow_op) {
-    if (!GetReadAheadPopulatedBuffer(cow_op)) {
-        SNAP_LOG(DEBUG) << " GetReadAheadPopulatedBuffer failed..."
-                        << " new_block: " << cow_op->new_block;
-        if (!ReadFromBaseDevice(cow_op)) {
-            return false;
-        }
-    }
-
-    return true;
-}
-
-bool WorkerThread::ProcessZeroOp() {
-    // Zero out the entire block
-    void* buffer = bufsink_.GetPayloadBuffer(BLOCK_SZ);
-    if (buffer == nullptr) {
-        SNAP_LOG(ERROR) << "ProcessZeroOp: Failed to get payload buffer";
-        return false;
-    }
-
-    memset(buffer, 0, BLOCK_SZ);
-    return true;
-}
-
-bool WorkerThread::ProcessCowOp(const CowOperation* cow_op) {
-    if (cow_op == nullptr) {
-        SNAP_LOG(ERROR) << "ProcessCowOp: Invalid cow_op";
-        return false;
-    }
-
-    switch (cow_op->type()) {
-        case kCowReplaceOp: {
-            return ProcessReplaceOp(cow_op);
-        }
-
-        case kCowZeroOp: {
-            return ProcessZeroOp();
-        }
-
-        case kCowCopyOp: {
-            return ProcessCopyOp(cow_op);
-        }
-
-        default: {
-            SNAP_LOG(ERROR) << "Unsupported operation-type found: "
-                            << static_cast<uint8_t>(cow_op->type());
-        }
-    }
-    return false;
-}
-
-int WorkerThread::ReadUnalignedSector(
-        sector_t sector, size_t size,
-        std::vector<std::pair<sector_t, const CowOperation*>>::iterator& it) {
-    size_t skip_sector_size = 0;
-
-    SNAP_LOG(DEBUG) << "ReadUnalignedSector: sector " << sector << " size: " << size
-                    << " Aligned sector: " << it->first;
-
-    if (!ProcessCowOp(it->second)) {
-        SNAP_LOG(ERROR) << "ReadUnalignedSector: " << sector << " failed of size: " << size
-                        << " Aligned sector: " << it->first;
-        return -1;
-    }
-
-    int num_sectors_skip = sector - it->first;
-
-    if (num_sectors_skip > 0) {
-        skip_sector_size = num_sectors_skip << SECTOR_SHIFT;
-        char* buffer = reinterpret_cast<char*>(bufsink_.GetBufPtr());
-        struct dm_user_message* msg = (struct dm_user_message*)(&(buffer[0]));
-
-        if (skip_sector_size == BLOCK_SZ) {
-            SNAP_LOG(ERROR) << "Invalid un-aligned IO request at sector: " << sector
-                            << " Base-sector: " << it->first;
-            return -1;
-        }
-
-        memmove(msg->payload.buf, (char*)msg->payload.buf + skip_sector_size,
-                (BLOCK_SZ - skip_sector_size));
-    }
-
-    bufsink_.ResetBufferOffset();
-    return std::min(size, (BLOCK_SZ - skip_sector_size));
-}
-
-/*
- * Read the data for a given COW Operation.
- *
- * Kernel can issue IO at a sector granularity.
- * Hence, an IO may end up with reading partial
- * data from a COW operation or we may also
- * end up with interspersed request between
- * two COW operations.
- *
- */
-int WorkerThread::ReadData(sector_t sector, size_t size) {
-    std::vector<std::pair<sector_t, const CowOperation*>>& chunk_vec = snapuserd_->GetChunkVec();
-    std::vector<std::pair<sector_t, const CowOperation*>>::iterator it;
-    /*
-     * chunk_map stores COW operation at 4k granularity.
-     * If the requested IO with the sector falls on the 4k
-     * boundary, then we can read the COW op directly without
-     * any issue.
-     *
-     * However, if the requested sector is not 4K aligned,
-     * then we will have the find the nearest COW operation
-     * and chop the 4K block to fetch the requested sector.
-     */
-    it = std::lower_bound(chunk_vec.begin(), chunk_vec.end(), std::make_pair(sector, nullptr),
-                          Snapuserd::compare);
-
-    bool read_end_of_device = false;
-    if (it == chunk_vec.end()) {
-        // |-------|-------|-------|
-        // 0       1       2       3
-        //
-        // Block 0 - op 1
-        // Block 1 - op 2
-        // Block 2 - op 3
-        //
-        // chunk_vec will have block 0, 1, 2 which maps to relavant COW ops.
-        //
-        // Each block is 4k bytes. Thus, the last block will span 8 sectors
-        // ranging till block 3 (However, block 3 won't be in chunk_vec as
-        // it doesn't have any mapping to COW ops. Now, if we get an I/O request for a sector
-        // spanning between block 2 and block 3, we need to step back
-        // and get hold of the last element.
-        //
-        // Additionally, dm-snapshot makes sure that I/O request beyond block 3
-        // will not be routed to the daemon. Hence, it is safe to assume that
-        // if a sector is not available in the chunk_vec, the I/O falls in the
-        // end of region.
-        it = std::prev(chunk_vec.end());
-        read_end_of_device = true;
-    }
-
-    // We didn't find the required sector; hence find the previous sector
-    // as lower_bound will gives us the value greater than
-    // the requested sector
-    if (it->first != sector) {
-        if (it != chunk_vec.begin() && !read_end_of_device) {
-            --it;
-        }
-
-        /*
-         * If the IO is spanned between two COW operations,
-         * split the IO into two parts:
-         *
-         * 1: Read the first part from the single COW op
-         * 2: Read the second part from the next COW op.
-         *
-         * Ex: Let's say we have a 1024 Bytes IO request.
-         *
-         * 0       COW OP-1  4096     COW OP-2  8192
-         * |******************|*******************|
-         *              |*****|*****|
-         *           3584           4608
-         *              <- 1024B - >
-         *
-         * We have two COW operations which are 4k blocks.
-         * The IO is requested for 1024 Bytes which are spanned
-         * between two COW operations. We will split this IO
-         * into two parts:
-         *
-         * 1: IO of size 512B from offset 3584 bytes (COW OP-1)
-         * 2: IO of size 512B from offset 4096 bytes (COW OP-2)
-         */
-        return ReadUnalignedSector(sector, size, it);
-    }
-
-    int num_ops = DIV_ROUND_UP(size, BLOCK_SZ);
-    sector_t read_sector = sector;
-    while (num_ops) {
-        // We have to make sure that the reads are
-        // sequential; there shouldn't be a data
-        // request merged with a metadata IO.
-        if (it->first != read_sector) {
-            SNAP_LOG(ERROR) << "Invalid IO request: read_sector: " << read_sector
-                            << " cow-op sector: " << it->first;
-            return -1;
-        } else if (!ProcessCowOp(it->second)) {
-            return -1;
-        }
-        num_ops -= 1;
-        read_sector += (BLOCK_SZ >> SECTOR_SHIFT);
-
-        it++;
-
-        if (it == chunk_vec.end() && num_ops) {
-            SNAP_LOG(ERROR) << "Invalid IO request at sector " << sector
-                            << " COW ops completed; pending read-request: " << num_ops;
-            return -1;
-        }
-        // Update the buffer offset
-        bufsink_.UpdateBufferOffset(BLOCK_SZ);
-    }
-
-    // Reset the buffer offset
-    bufsink_.ResetBufferOffset();
-    return size;
-}
-
-/*
- * dm-snap does prefetch reads while reading disk-exceptions.
- * By default, prefetch value is set to 12; this means that
- * dm-snap will issue 12 areas wherein each area is a 4k page
- * of disk-exceptions.
- *
- * If during prefetch, if the chunk-id seen is beyond the
- * actual number of metadata page, fill the buffer with zero.
- * When dm-snap starts parsing the buffer, it will stop
- * reading metadata page once the buffer content is zero.
- */
-bool WorkerThread::ZerofillDiskExceptions(size_t read_size) {
-    size_t size = exceptions_per_area_ * sizeof(struct disk_exception);
-
-    if (read_size > size) {
-        return false;
-    }
-
-    void* buffer = bufsink_.GetPayloadBuffer(size);
-    if (buffer == nullptr) {
-        SNAP_LOG(ERROR) << "ZerofillDiskExceptions: Failed to get payload buffer";
-        return false;
-    }
-
-    memset(buffer, 0, size);
-    return true;
-}
-
-/*
- * A disk exception is a simple mapping of old_chunk to new_chunk.
- * When dm-snapshot device is created, kernel requests these mapping.
- *
- * Each disk exception is of size 16 bytes. Thus a single 4k page can
- * have:
- *
- * exceptions_per_area_ = 4096/16 = 256. This entire 4k page
- * is considered a metadata page and it is represented by chunk ID.
- *
- * Convert the chunk ID to index into the vector which gives us
- * the metadata page.
- */
-bool WorkerThread::ReadDiskExceptions(chunk_t chunk, size_t read_size) {
-    uint32_t stride = exceptions_per_area_ + 1;
-    size_t size;
-    const std::vector<std::unique_ptr<uint8_t[]>>& vec = snapuserd_->GetMetadataVec();
-
-    // ChunkID to vector index
-    lldiv_t divresult = lldiv(chunk, stride);
-
-    if (divresult.quot < vec.size()) {
-        size = exceptions_per_area_ * sizeof(struct disk_exception);
-
-        if (read_size != size) {
-            SNAP_LOG(ERROR) << "ReadDiskExceptions: read_size: " << read_size
-                            << " does not match with size: " << size;
-            return false;
-        }
-
-        void* buffer = bufsink_.GetPayloadBuffer(size);
-        if (buffer == nullptr) {
-            SNAP_LOG(ERROR) << "ReadDiskExceptions: Failed to get payload buffer of size: " << size;
-            return false;
-        }
-
-        memcpy(buffer, vec[divresult.quot].get(), size);
-    } else {
-        return ZerofillDiskExceptions(read_size);
-    }
-
-    return true;
-}
-
-loff_t WorkerThread::GetMergeStartOffset(void* merged_buffer, void* unmerged_buffer,
-                                         int* unmerged_exceptions) {
-    loff_t offset = 0;
-    *unmerged_exceptions = 0;
-
-    while (*unmerged_exceptions <= exceptions_per_area_) {
-        struct disk_exception* merged_de =
-                reinterpret_cast<struct disk_exception*>((char*)merged_buffer + offset);
-        struct disk_exception* cow_de =
-                reinterpret_cast<struct disk_exception*>((char*)unmerged_buffer + offset);
-
-        // Unmerged op by the kernel
-        if (merged_de->old_chunk != 0 || merged_de->new_chunk != 0) {
-            if (!(merged_de->old_chunk == cow_de->old_chunk)) {
-                SNAP_LOG(ERROR) << "GetMergeStartOffset: merged_de->old_chunk: "
-                                << merged_de->old_chunk
-                                << "cow_de->old_chunk: " << cow_de->old_chunk;
-                return -1;
-            }
-
-            if (!(merged_de->new_chunk == cow_de->new_chunk)) {
-                SNAP_LOG(ERROR) << "GetMergeStartOffset: merged_de->new_chunk: "
-                                << merged_de->new_chunk
-                                << "cow_de->new_chunk: " << cow_de->new_chunk;
-                return -1;
-            }
-
-            offset += sizeof(struct disk_exception);
-            *unmerged_exceptions += 1;
-            continue;
-        }
-
-        break;
-    }
-
-    SNAP_LOG(DEBUG) << "Unmerged_Exceptions: " << *unmerged_exceptions << " Offset: " << offset;
-    return offset;
-}
-
-int WorkerThread::GetNumberOfMergedOps(void* merged_buffer, void* unmerged_buffer, loff_t offset,
-                                       int unmerged_exceptions, bool* ordered_op, bool* commit) {
-    int merged_ops_cur_iter = 0;
-    std::unordered_map<uint64_t, void*>& read_ahead_buffer_map = snapuserd_->GetReadAheadMap();
-    *ordered_op = false;
-    std::vector<std::pair<sector_t, const CowOperation*>>& chunk_vec = snapuserd_->GetChunkVec();
-
-    // Find the operations which are merged in this cycle.
-    while ((unmerged_exceptions + merged_ops_cur_iter) < exceptions_per_area_) {
-        struct disk_exception* merged_de =
-                reinterpret_cast<struct disk_exception*>((char*)merged_buffer + offset);
-        struct disk_exception* cow_de =
-                reinterpret_cast<struct disk_exception*>((char*)unmerged_buffer + offset);
-
-        if (!(merged_de->new_chunk == 0)) {
-            SNAP_LOG(ERROR) << "GetNumberOfMergedOps: Invalid new-chunk: " << merged_de->new_chunk;
-            return -1;
-        }
-
-        if (!(merged_de->old_chunk == 0)) {
-            SNAP_LOG(ERROR) << "GetNumberOfMergedOps: Invalid old-chunk: " << merged_de->old_chunk;
-            return -1;
-        }
-
-        if (cow_de->new_chunk != 0) {
-            merged_ops_cur_iter += 1;
-            offset += sizeof(struct disk_exception);
-            auto it = std::lower_bound(chunk_vec.begin(), chunk_vec.end(),
-                                       std::make_pair(ChunkToSector(cow_de->new_chunk), nullptr),
-                                       Snapuserd::compare);
-
-            if (!(it != chunk_vec.end())) {
-                SNAP_LOG(ERROR) << "Sector not found: " << ChunkToSector(cow_de->new_chunk);
-                return -1;
-            }
-
-            if (!(it->first == ChunkToSector(cow_de->new_chunk))) {
-                SNAP_LOG(ERROR) << "Invalid sector: " << ChunkToSector(cow_de->new_chunk);
-                return -1;
-            }
-            const CowOperation* cow_op = it->second;
-
-            if (snapuserd_->IsReadAheadFeaturePresent() && IsOrderedOp(*cow_op)) {
-                *ordered_op = true;
-                // Every single ordered operation has to come from read-ahead
-                // cache.
-                if (read_ahead_buffer_map.find(cow_op->new_block) == read_ahead_buffer_map.end()) {
-                    SNAP_LOG(ERROR)
-                            << " Block: " << cow_op->new_block << " not found in read-ahead cache"
-                            << " Op: " << *cow_op;
-                    return -1;
-                }
-                // If this is a final block merged in the read-ahead buffer
-                // region, notify the read-ahead thread to make forward
-                // progress
-                if (cow_op->new_block == snapuserd_->GetFinalBlockMerged()) {
-                    *commit = true;
-                }
-            }
-
-            // zero out to indicate that operation is merged.
-            cow_de->old_chunk = 0;
-            cow_de->new_chunk = 0;
-        } else if (cow_de->old_chunk == 0) {
-            // Already merged op in previous iteration or
-            // This could also represent a partially filled area.
-            //
-            // If the op was merged in previous cycle, we don't have
-            // to count them.
-            break;
-        } else {
-            SNAP_LOG(ERROR) << "Error in merge operation. Found invalid metadata: "
-                            << " merged_de-old-chunk: " << merged_de->old_chunk
-                            << " merged_de-new-chunk: " << merged_de->new_chunk
-                            << " cow_de-old-chunk: " << cow_de->old_chunk
-                            << " cow_de-new-chunk: " << cow_de->new_chunk
-                            << " unmerged_exceptions: " << unmerged_exceptions
-                            << " merged_ops_cur_iter: " << merged_ops_cur_iter
-                            << " offset: " << offset;
-            return -1;
-        }
-    }
-    return merged_ops_cur_iter;
-}
-
-bool WorkerThread::ProcessMergeComplete(chunk_t chunk, void* buffer) {
-    uint32_t stride = exceptions_per_area_ + 1;
-    const std::vector<std::unique_ptr<uint8_t[]>>& vec = snapuserd_->GetMetadataVec();
-    bool ordered_op = false;
-    bool commit = false;
-
-    // ChunkID to vector index
-    lldiv_t divresult = lldiv(chunk, stride);
-
-    if (!(divresult.quot < vec.size())) {
-        SNAP_LOG(ERROR) << "ProcessMergeComplete: Invalid chunk: " << chunk
-                        << " Metadata-Index: " << divresult.quot << " Area-size: " << vec.size();
-        return false;
-    }
-
-    SNAP_LOG(DEBUG) << "ProcessMergeComplete: chunk: " << chunk
-                    << " Metadata-Index: " << divresult.quot;
-
-    int unmerged_exceptions = 0;
-    loff_t offset = GetMergeStartOffset(buffer, vec[divresult.quot].get(), &unmerged_exceptions);
-
-    if (offset < 0) {
-        SNAP_LOG(ERROR) << "GetMergeStartOffset failed: unmerged_exceptions: "
-                        << unmerged_exceptions;
-        return false;
-    }
-
-    int merged_ops_cur_iter = GetNumberOfMergedOps(buffer, vec[divresult.quot].get(), offset,
-                                                   unmerged_exceptions, &ordered_op, &commit);
-
-    // There should be at least one operation merged in this cycle
-    if (!(merged_ops_cur_iter > 0)) {
-        SNAP_LOG(ERROR) << "Merge operation failed: " << merged_ops_cur_iter;
-        return false;
-    }
-
-    if (ordered_op) {
-        if (commit) {
-            // Push the flushing logic to read-ahead thread so that merge thread
-            // can make forward progress. Sync will happen in the background
-            snapuserd_->StartReadAhead();
-        }
-    } else {
-        // Non-copy ops and all ops in older COW format
-        if (!snapuserd_->CommitMerge(merged_ops_cur_iter)) {
-            SNAP_LOG(ERROR) << "CommitMerge failed...";
-            return false;
-        }
-    }
-
-    SNAP_LOG(DEBUG) << "Merge success: " << merged_ops_cur_iter << "chunk: " << chunk;
-    return true;
-}
-
-// Read Header from dm-user misc device. This gives
-// us the sector number for which IO is issued by dm-snapshot device
-bool WorkerThread::ReadDmUserHeader() {
-    if (!android::base::ReadFully(ctrl_fd_, bufsink_.GetBufPtr(), sizeof(struct dm_user_header))) {
-        if (errno != ENOTBLK) {
-            SNAP_PLOG(ERROR) << "Control-read failed";
-        }
-
-        return false;
-    }
-
-    return true;
-}
-
-// Send the payload/data back to dm-user misc device.
-bool WorkerThread::WriteDmUserPayload(size_t size, bool header_response) {
-    size_t payload_size = size;
-    void* buf = bufsink_.GetPayloadBufPtr();
-    if (header_response) {
-        payload_size += sizeof(struct dm_user_header);
-        buf = bufsink_.GetBufPtr();
-    }
-
-    if (!android::base::WriteFully(ctrl_fd_, buf, payload_size)) {
-        SNAP_PLOG(ERROR) << "Write to dm-user failed size: " << payload_size;
-        return false;
-    }
-
-    return true;
-}
-
-bool WorkerThread::ReadDmUserPayload(void* buffer, size_t size) {
-    if (!android::base::ReadFully(ctrl_fd_, buffer, size)) {
-        SNAP_PLOG(ERROR) << "ReadDmUserPayload failed size: " << size;
-        return false;
-    }
-
-    return true;
-}
-
-bool WorkerThread::DmuserWriteRequest() {
-    struct dm_user_header* header = bufsink_.GetHeaderPtr();
-
-    // device mapper has the capability to allow
-    // targets to flush the cache when writes are completed. This
-    // is controlled by each target by a flag "flush_supported".
-    // This flag is set by dm-user. When flush is supported,
-    // a number of zero-length bio's will be submitted to
-    // the target for the purpose of flushing cache. It is the
-    // responsibility of the target driver - which is dm-user in this
-    // case, to remap these bio's to the underlying device. Since,
-    // there is no underlying device for dm-user, this zero length
-    // bio's gets routed to daemon.
-    //
-    // Flush operations are generated post merge by dm-snap by having
-    // REQ_PREFLUSH flag set. Snapuser daemon doesn't have anything
-    // to flush per se; hence, just respond back with a success message.
-    if (header->sector == 0) {
-        if (!(header->len == 0)) {
-            SNAP_LOG(ERROR) << "Invalid header length received from sector 0: " << header->len;
-            header->type = DM_USER_RESP_ERROR;
-        } else {
-            header->type = DM_USER_RESP_SUCCESS;
-        }
-
-        if (!WriteDmUserPayload(0, true)) {
-            return false;
-        }
-        return true;
-    }
-
-    std::vector<std::pair<sector_t, const CowOperation*>>& chunk_vec = snapuserd_->GetChunkVec();
-    size_t remaining_size = header->len;
-    size_t read_size = std::min(PAYLOAD_SIZE, remaining_size);
-
-    chunk_t chunk = SectorToChunk(header->sector);
-    auto it = std::lower_bound(chunk_vec.begin(), chunk_vec.end(),
-                               std::make_pair(header->sector, nullptr), Snapuserd::compare);
-
-    bool not_found = (it == chunk_vec.end() || it->first != header->sector);
-
-    if (not_found) {
-        void* buffer = bufsink_.GetPayloadBuffer(read_size);
-        if (buffer == nullptr) {
-            SNAP_LOG(ERROR) << "DmuserWriteRequest: Failed to get payload buffer of size: "
-                            << read_size;
-            header->type = DM_USER_RESP_ERROR;
-        } else {
-            header->type = DM_USER_RESP_SUCCESS;
-
-            if (!ReadDmUserPayload(buffer, read_size)) {
-                SNAP_LOG(ERROR) << "ReadDmUserPayload failed for chunk id: " << chunk
-                                << "Sector: " << header->sector;
-                header->type = DM_USER_RESP_ERROR;
-            }
-
-            if (header->type == DM_USER_RESP_SUCCESS && !ProcessMergeComplete(chunk, buffer)) {
-                SNAP_LOG(ERROR) << "ProcessMergeComplete failed for chunk id: " << chunk
-                                << "Sector: " << header->sector;
-                header->type = DM_USER_RESP_ERROR;
-            }
-        }
-    } else {
-        SNAP_LOG(ERROR) << "DmuserWriteRequest: Invalid sector received: header->sector";
-        header->type = DM_USER_RESP_ERROR;
-    }
-
-    if (!WriteDmUserPayload(0, true)) {
-        return false;
-    }
-
-    return true;
-}
-
-bool WorkerThread::DmuserReadRequest() {
-    struct dm_user_header* header = bufsink_.GetHeaderPtr();
-    size_t remaining_size = header->len;
-    loff_t offset = 0;
-    sector_t sector = header->sector;
-    std::vector<std::pair<sector_t, const CowOperation*>>& chunk_vec = snapuserd_->GetChunkVec();
-    bool header_response = true;
-    do {
-        size_t read_size = std::min(PAYLOAD_SIZE, remaining_size);
-
-        int ret = read_size;
-        header->type = DM_USER_RESP_SUCCESS;
-        chunk_t chunk = SectorToChunk(header->sector);
-
-        // Request to sector 0 is always for kernel
-        // representation of COW header. This IO should be only
-        // once during dm-snapshot device creation. We should
-        // never see multiple IO requests. Additionally this IO
-        // will always be a single 4k.
-        if (header->sector == 0) {
-            if (read_size == BLOCK_SZ) {
-                ConstructKernelCowHeader();
-                SNAP_LOG(DEBUG) << "Kernel header constructed";
-            } else {
-                SNAP_LOG(ERROR) << "Invalid read_size: " << read_size << " for sector 0";
-                header->type = DM_USER_RESP_ERROR;
-            }
-        } else {
-            auto it = std::lower_bound(chunk_vec.begin(), chunk_vec.end(),
-                                       std::make_pair(header->sector, nullptr), Snapuserd::compare);
-            bool not_found = (it == chunk_vec.end() || it->first != header->sector);
-            if (!offset && (read_size == BLOCK_SZ) && not_found) {
-                if (!ReadDiskExceptions(chunk, read_size)) {
-                    SNAP_LOG(ERROR) << "ReadDiskExceptions failed for chunk id: " << chunk
-                                    << "Sector: " << header->sector;
-                    header->type = DM_USER_RESP_ERROR;
-                } else {
-                    SNAP_LOG(DEBUG) << "ReadDiskExceptions success for chunk id: " << chunk
-                                    << "Sector: " << header->sector;
-                }
-            } else {
-                chunk_t num_sectors_read = (offset >> SECTOR_SHIFT);
-
-                ret = ReadData(sector + num_sectors_read, read_size);
-                if (ret < 0) {
-                    SNAP_LOG(ERROR) << "ReadData failed for chunk id: " << chunk
-                                    << " Sector: " << (sector + num_sectors_read)
-                                    << " size: " << read_size << " header-len: " << header->len;
-                    header->type = DM_USER_RESP_ERROR;
-                } else {
-                    SNAP_LOG(DEBUG) << "ReadData success for chunk id: " << chunk
-                                    << "Sector: " << header->sector;
-                }
-            }
-        }
-
-        // Just return the header if it is an error
-        if (header->type == DM_USER_RESP_ERROR) {
-            SNAP_LOG(ERROR) << "IO read request failed...";
-            ret = 0;
-        }
-
-        if (!header_response) {
-            CHECK(header->type == DM_USER_RESP_SUCCESS)
-                    << " failed for sector: " << sector << " header->len: " << header->len
-                    << " remaining_size: " << remaining_size;
-        }
-
-        // Daemon will not be terminated if there is any error. We will
-        // just send the error back to dm-user.
-        if (!WriteDmUserPayload(ret, header_response)) {
-            return false;
-        }
-
-        if (header->type == DM_USER_RESP_ERROR) {
-            break;
-        }
-
-        remaining_size -= ret;
-        offset += ret;
-        header_response = false;
-    } while (remaining_size > 0);
-
-    return true;
-}
-
-void WorkerThread::InitializeBufsink() {
-    // Allocate the buffer which is used to communicate between
-    // daemon and dm-user. The buffer comprises of header and a fixed payload.
-    // If the dm-user requests a big IO, the IO will be broken into chunks
-    // of PAYLOAD_SIZE.
-    size_t buf_size = sizeof(struct dm_user_header) + PAYLOAD_SIZE;
-    bufsink_.Initialize(buf_size);
-}
-
-bool WorkerThread::RunThread() {
-    InitializeBufsink();
-
-    if (!InitializeFds()) {
-        return false;
-    }
-
-    if (!InitReader()) {
-        return false;
-    }
-
-    // Start serving IO
-    while (true) {
-        if (!ProcessIORequest()) {
-            break;
-        }
-    }
-
-    CloseFds();
-    reader_->CloseCowFd();
-
-    return true;
-}
-
-bool WorkerThread::ProcessIORequest() {
-    struct dm_user_header* header = bufsink_.GetHeaderPtr();
-
-    if (!ReadDmUserHeader()) {
-        return false;
-    }
-
-    SNAP_LOG(DEBUG) << "Daemon: msg->seq: " << std::dec << header->seq;
-    SNAP_LOG(DEBUG) << "Daemon: msg->len: " << std::dec << header->len;
-    SNAP_LOG(DEBUG) << "Daemon: msg->sector: " << std::dec << header->sector;
-    SNAP_LOG(DEBUG) << "Daemon: msg->type: " << std::dec << header->type;
-    SNAP_LOG(DEBUG) << "Daemon: msg->flags: " << std::dec << header->flags;
-
-    switch (header->type) {
-        case DM_USER_REQ_MAP_READ: {
-            if (!DmuserReadRequest()) {
-                return false;
-            }
-            break;
-        }
-
-        case DM_USER_REQ_MAP_WRITE: {
-            if (!DmuserWriteRequest()) {
-                return false;
-            }
-            break;
-        }
-    }
-
-    return true;
-}
-
-}  // namespace snapshot
-}  // namespace android
diff --git a/fs_mgr/libsnapshot/snapuserd/snapuserd_daemon.cpp b/fs_mgr/libsnapshot/snapuserd/snapuserd_daemon.cpp
index 36dad33..0ebe543 100644
--- a/fs_mgr/libsnapshot/snapuserd/snapuserd_daemon.cpp
+++ b/fs_mgr/libsnapshot/snapuserd/snapuserd_daemon.cpp
@@ -38,20 +38,20 @@
     const std::string vendor_release =
             android::base::GetProperty("ro.vendor.build.version.release_or_codename", UNKNOWN);
 
-    // No user-space snapshots if vendor partition is on Android 12
+    // If the vendor is on Android S, install process will forcefully take the
+    // userspace snapshots path.
+    //
+    // We will not reach here post OTA reboot as the binary will be from vendor
+    // ramdisk which is on Android S.
     if (vendor_release.find("12") != std::string::npos) {
-        LOG(INFO) << "Userspace snapshots disabled as vendor partition is on Android: "
+        LOG(INFO) << "Userspace snapshots enabled as vendor partition is on Android: "
                   << vendor_release;
-        return false;
+        return true;
     }
 
     return android::base::GetBoolProperty("ro.virtual_ab.userspace.snapshots.enabled", false);
 }
 
-bool Daemon::IsDmSnapshotTestingEnabled() {
-    return android::base::GetBoolProperty("snapuserd.test.dm.snapshots", false);
-}
-
 bool Daemon::StartDaemon(int argc, char** argv) {
     int arg_start = gflags::ParseCommandLineFlags(&argc, &argv, true);
 
@@ -65,16 +65,16 @@
     // stage init and hence use the command line flags to get the information.
     bool user_snapshots = FLAGS_user_snapshot;
     if (!user_snapshots) {
-        user_snapshots = (!IsDmSnapshotTestingEnabled() && IsUserspaceSnapshotsEnabled());
+        user_snapshots = IsUserspaceSnapshotsEnabled();
     }
 
     if (user_snapshots) {
         LOG(INFO) << "Starting daemon for user-space snapshots.....";
         return StartServerForUserspaceSnapshots(arg_start, argc, argv);
     } else {
-        LOG(INFO) << "Starting daemon for dm-snapshots.....";
-        return StartServerForDmSnapshot(arg_start, argc, argv);
+        LOG(ERROR) << "Userspace snapshots not enabled. No support for legacy snapshots";
     }
+    return false;
 }
 
 bool Daemon::StartServerForUserspaceSnapshots(int arg_start, int argc, char** argv) {
@@ -130,48 +130,6 @@
     return user_server_.WaitForSocket();
 }
 
-bool Daemon::StartServerForDmSnapshot(int arg_start, int argc, char** argv) {
-    sigfillset(&signal_mask_);
-    sigdelset(&signal_mask_, SIGINT);
-    sigdelset(&signal_mask_, SIGTERM);
-    sigdelset(&signal_mask_, SIGUSR1);
-
-    // Masking signals here ensure that after this point, we won't handle INT/TERM
-    // until after we call into ppoll()
-    signal(SIGINT, Daemon::SignalHandler);
-    signal(SIGTERM, Daemon::SignalHandler);
-    signal(SIGPIPE, Daemon::SignalHandler);
-    signal(SIGUSR1, Daemon::SignalHandler);
-
-    MaskAllSignalsExceptIntAndTerm();
-
-    if (FLAGS_socket_handoff) {
-        return server_.RunForSocketHandoff();
-    }
-    if (!FLAGS_no_socket) {
-        if (!server_.Start(FLAGS_socket)) {
-            return false;
-        }
-        return server_.Run();
-    }
-
-    for (int i = arg_start; i < argc; i++) {
-        auto parts = android::base::Split(argv[i], ",");
-        if (parts.size() != 3) {
-            LOG(ERROR) << "Malformed message, expected three sub-arguments.";
-            return false;
-        }
-        auto handler = server_.AddHandler(parts[0], parts[1], parts[2]);
-        if (!handler || !server_.StartHandler(handler)) {
-            return false;
-        }
-    }
-
-    // Skip the accept() call to avoid spurious log spam. The server will still
-    // run until all handlers have completed.
-    return server_.WaitForSocket();
-}
-
 void Daemon::MaskAllSignalsExceptIntAndTerm() {
     sigset_t signal_mask;
     sigfillset(&signal_mask);
@@ -198,16 +156,12 @@
     // and verify it through a temp variable.
     if (user_server_.IsServerRunning()) {
         user_server_.Interrupt();
-    } else {
-        server_.Interrupt();
     }
 }
 
 void Daemon::ReceivedSocketSignal() {
     if (user_server_.IsServerRunning()) {
         user_server_.ReceivedSocketSignal();
-    } else {
-        server_.ReceivedSocketSignal();
     }
 }
 
diff --git a/fs_mgr/libsnapshot/snapuserd/snapuserd_daemon.h b/fs_mgr/libsnapshot/snapuserd/snapuserd_daemon.h
index cf3b917..303e394 100644
--- a/fs_mgr/libsnapshot/snapuserd/snapuserd_daemon.h
+++ b/fs_mgr/libsnapshot/snapuserd/snapuserd_daemon.h
@@ -19,7 +19,6 @@
 #include <string>
 #include <vector>
 
-#include "dm-snapshot-merge/snapuserd_server.h"
 #include "user-space-merge/snapuserd_server.h"
 
 namespace android {
@@ -36,12 +35,10 @@
         return instance;
     }
 
-    bool StartServerForDmSnapshot(int arg_start, int argc, char** argv);
     bool StartServerForUserspaceSnapshots(int arg_start, int argc, char** argv);
     void Interrupt();
     void ReceivedSocketSignal();
     bool IsUserspaceSnapshotsEnabled();
-    bool IsDmSnapshotTestingEnabled();
     bool StartDaemon(int argc, char** argv);
 
   private:
@@ -51,7 +48,6 @@
     Daemon(Daemon const&) = delete;
     void operator=(Daemon const&) = delete;
 
-    SnapuserdServer server_;
     UserSnapshotServer user_server_;
     void MaskAllSignalsExceptIntAndTerm();
     void MaskAllSignals();
diff --git a/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_test.cpp b/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_test.cpp
index 76b44b4..d05df82 100644
--- a/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_test.cpp
+++ b/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_test.cpp
@@ -126,7 +126,8 @@
 }
 
 std::unique_ptr<ICowWriter> SnapuserdTestBase::CreateCowDeviceInternal() {
-    cow_system_ = std::make_unique<TemporaryFile>();
+    std::string path = android::base::GetExecutableDirectory();
+    cow_system_ = std::make_unique<TemporaryFile>(path);
 
     CowOptions options;
     options.compression = "gz";
@@ -147,7 +148,8 @@
     options.batch_write = true;
     options.compression_factor = params.block_size;
 
-    cow_system_ = std::make_unique<TemporaryFile>();
+    std::string path = android::base::GetExecutableDirectory();
+    cow_system_ = std::make_unique<TemporaryFile>(path);
 
     unique_fd fd(cow_system_->fd);
     cow_system_->fd = -1;
@@ -989,6 +991,7 @@
 void SnapuserdVariableBlockSizeTest::CreateV3CowDeviceForVariableBlockSize() {
     auto writer = CreateV3Cow();
 
+    ASSERT_NE(writer, nullptr);
     size_t total_data_to_write = size_;
 
     size_t total_blocks_to_write = total_data_to_write / BLOCK_SZ;
@@ -1337,6 +1340,7 @@
 void HandlerTestV3::SetUpV3Cow() {
     auto writer = CreateV3Cow();
 
+    ASSERT_NE(writer, nullptr);
     size_t total_data_to_write = size_;
 
     size_t total_blocks_to_write = total_data_to_write / BLOCK_SZ;
diff --git a/fs_mgr/libsnapshot/utility.cpp b/fs_mgr/libsnapshot/utility.cpp
index 1ffa89c..fe2d95c 100644
--- a/fs_mgr/libsnapshot/utility.cpp
+++ b/fs_mgr/libsnapshot/utility.cpp
@@ -230,11 +230,7 @@
     return fetcher->GetBoolProperty("ro.virtual_ab.userspace.snapshots.enabled", false);
 }
 
-bool CanUseUserspaceSnapshots() {
-    if (!GetUserspaceSnapshotsEnabledProperty()) {
-        return false;
-    }
-
+bool IsVendorFromAndroid12() {
     auto fetcher = IPropertyFetcher::GetInstance();
 
     const std::string UNKNOWN = "unknown";
@@ -243,8 +239,15 @@
 
     // No user-space snapshots if vendor partition is on Android 12
     if (vendor_release.find("12") != std::string::npos) {
-        LOG(INFO) << "Userspace snapshots disabled as vendor partition is on Android: "
-                  << vendor_release;
+        return true;
+    }
+
+    return false;
+}
+
+bool CanUseUserspaceSnapshots() {
+    if (!GetUserspaceSnapshotsEnabledProperty()) {
+        LOG(INFO) << "Virtual A/B - Userspace snapshots disabled";
         return false;
     }
 
diff --git a/fs_mgr/libsnapshot/utility.h b/fs_mgr/libsnapshot/utility.h
index 370f3c4..f956a05 100644
--- a/fs_mgr/libsnapshot/utility.h
+++ b/fs_mgr/libsnapshot/utility.h
@@ -136,6 +136,7 @@
 
 bool CanUseUserspaceSnapshots();
 bool IsDmSnapshotTestingEnabled();
+bool IsVendorFromAndroid12();
 
 // Swap the suffix of a partition name.
 std::string GetOtherPartitionName(const std::string& name);
diff --git a/fs_mgr/libsnapshot/vts_ota_config_test.cpp b/fs_mgr/libsnapshot/vts_ota_config_test.cpp
index d387eb3..b5618c4 100755
--- a/fs_mgr/libsnapshot/vts_ota_config_test.cpp
+++ b/fs_mgr/libsnapshot/vts_ota_config_test.cpp
@@ -21,6 +21,7 @@
     return android::base::GetIntProperty("ro.vendor.api_level", -1);
 }
 
+// @VsrTest = 3.7.6
 TEST(VAB, Enabled) {
     if (!android::base::GetBoolProperty("ro.build.ab_update", false) && (GetVsrLevel() < __ANDROID_API_T__)) {
         GTEST_SKIP();
diff --git a/fs_mgr/tools/dmctl.cpp b/fs_mgr/tools/dmctl.cpp
index 9dc8c24..f843821 100644
--- a/fs_mgr/tools/dmctl.cpp
+++ b/fs_mgr/tools/dmctl.cpp
@@ -52,6 +52,7 @@
     std::cerr << "  list <devices | targets> [-v]" << std::endl;
     std::cerr << "  getpath <dm-name>" << std::endl;
     std::cerr << "  getuuid <dm-name>" << std::endl;
+    std::cerr << "  ima <dm-name>" << std::endl;
     std::cerr << "  info <dm-name>" << std::endl;
     std::cerr << "  replace <dm-name> <targets...>" << std::endl;
     std::cerr << "  status <dm-name>" << std::endl;
@@ -508,7 +509,14 @@
                       << std::endl;
             return -EINVAL;
         }
+    } else if (mode == "ima") {
+        if (!dm.GetTableStatusIma(argv[0], &table)) {
+            std::cerr << "Could not query table status of device \"" << argv[0] << "\"."
+                      << std::endl;
+            return -EINVAL;
+        }
     }
+
     std::cout << "Targets in the device-mapper table for " << argv[0] << ":" << std::endl;
     for (const auto& target : table) {
         std::cout << target.spec.sector_start << "-"
@@ -530,6 +538,10 @@
     return DumpTable("status", argc, argv);
 }
 
+static int ImaCmdHandler(int argc, char** argv) {
+    return DumpTable("ima", argc, argv);
+}
+
 static int ResumeCmdHandler(int argc, char** argv) {
     if (argc != 1) {
         std::cerr << "Invalid arguments, see \'dmctl help\'" << std::endl;
@@ -570,6 +582,7 @@
         {"info", InfoCmdHandler},
         {"table", TableCmdHandler},
         {"status", StatusCmdHandler},
+        {"ima", ImaCmdHandler},
         {"resume", ResumeCmdHandler},
         {"suspend", SuspendCmdHandler},
         // clang-format on
diff --git a/init/Android.bp b/init/Android.bp
index c3abefe..d4b7fab 100644
--- a/init/Android.bp
+++ b/init/Android.bp
@@ -162,6 +162,7 @@
     },
     static_libs: [
         "libavb",
+        "libavf_cc_flags",
         "libbootloader_message",
         "libc++fs",
         "libcgrouprc_format",
@@ -309,6 +310,7 @@
     name: "init_second_stage",
     defaults: ["init_second_stage_defaults"],
     static_libs: ["libinit"],
+    visibility: ["//visibility:any_system_partition"],
 }
 
 cc_binary {
@@ -359,6 +361,7 @@
     static_libs: [
         "libc++fs",
         "libfs_avb",
+        "libavf_cc_flags",
         "libfs_mgr",
         "libfec",
         "libfec_rs",
@@ -459,7 +462,10 @@
 
 cc_binary {
     name: "init_first_stage.microdroid",
-    defaults: ["init_first_stage_defaults"],
+    defaults: [
+        "avf_build_flags_cc",
+        "init_first_stage_defaults",
+    ],
     cflags: ["-DMICRODROID=1"],
     installable: false,
 }
diff --git a/init/block_dev_initializer.cpp b/init/block_dev_initializer.cpp
index 05e00ed..a686d05 100644
--- a/init/block_dev_initializer.cpp
+++ b/init/block_dev_initializer.cpp
@@ -132,11 +132,19 @@
 bool BlockDevInitializer::InitDmDevice(const std::string& device) {
     const std::string device_name(basename(device.c_str()));
     const std::string syspath = "/sys/block/" + device_name;
+    return InitDevice(syspath, device_name);
+}
+
+bool BlockDevInitializer::InitPlatformDevice(const std::string& dev_name) {
+    return InitDevice("/sys/devices/platform", dev_name);
+}
+
+bool BlockDevInitializer::InitDevice(const std::string& syspath, const std::string& device_name) {
     bool found = false;
 
-    auto uevent_callback = [&device_name, &device, this, &found](const Uevent& uevent) {
+    auto uevent_callback = [&device_name, this, &found](const Uevent& uevent) {
         if (uevent.device_name == device_name) {
-            LOG(VERBOSE) << "Creating device-mapper device : " << device;
+            LOG(VERBOSE) << "Creating device : " << device_name;
             device_handler_->HandleUevent(uevent);
             found = true;
             return ListenerAction::kStop;
@@ -146,13 +154,13 @@
 
     uevent_listener_.RegenerateUeventsForPath(syspath, uevent_callback);
     if (!found) {
-        LOG(INFO) << "dm device '" << device << "' not found in /sys, waiting for its uevent";
+        LOG(INFO) << "device '" << device_name << "' not found in /sys, waiting for its uevent";
         Timer t;
         uevent_listener_.Poll(uevent_callback, 10s);
-        LOG(INFO) << "wait for dm device '" << device << "' returned after " << t;
+        LOG(INFO) << "wait for device '" << device_name << "' returned after " << t;
     }
     if (!found) {
-        LOG(ERROR) << "dm device '" << device << "' not found after polling timeout";
+        LOG(ERROR) << "device '" << device_name << "' not found after polling timeout";
         return false;
     }
     return true;
diff --git a/init/block_dev_initializer.h b/init/block_dev_initializer.h
index ec39ce0..d5b1f60 100644
--- a/init/block_dev_initializer.h
+++ b/init/block_dev_initializer.h
@@ -24,6 +24,7 @@
 namespace android {
 namespace init {
 
+// TODO: should this be renamed to FirstStageDevInitialize?
 class BlockDevInitializer final {
   public:
     BlockDevInitializer();
@@ -32,11 +33,13 @@
     bool InitDmUser(const std::string& name);
     bool InitDevices(std::set<std::string> devices);
     bool InitDmDevice(const std::string& device);
+    bool InitPlatformDevice(const std::string& device);
 
   private:
     ListenerAction HandleUevent(const Uevent& uevent, std::set<std::string>* devices);
 
     bool InitMiscDevice(const std::string& name);
+    bool InitDevice(const std::string& syspath, const std::string& device);
 
     std::unique_ptr<DeviceHandler> device_handler_;
     UeventListener uevent_listener_;
diff --git a/init/first_stage_init.cpp b/init/first_stage_init.cpp
index c4d0f75..bfe636b 100644
--- a/init/first_stage_init.cpp
+++ b/init/first_stage_init.cpp
@@ -37,6 +37,7 @@
 #include <android-base/file.h>
 #include <android-base/logging.h>
 #include <android-base/stringprintf.h>
+#include <android/avf_cc_flags.h>
 #include <modprobe/modprobe.h>
 #include <private/android_filesystem_config.h>
 
@@ -385,7 +386,12 @@
     // /second_stage_resources is used to preserve files from first to second
     // stage init
     CHECKCALL(mount("tmpfs", kSecondStageRes, "tmpfs", MS_NOEXEC | MS_NOSUID | MS_NODEV,
-                    "mode=0755,uid=0,gid=0"))
+                    "mode=0755,uid=0,gid=0"));
+
+    if (IsMicrodroid() && android::virtualization::IsOpenDiceChangesFlagEnabled()) {
+        CHECKCALL(mount("tmpfs", "/microdroid_resources", "tmpfs", MS_NOEXEC | MS_NOSUID | MS_NODEV,
+                        "mode=0750,uid=0,gid=0"));
+    }
 #undef CHECKCALL
 
     SetStdioToDevNull(argv);
@@ -402,18 +408,6 @@
 
     LOG(INFO) << "init first stage started!";
 
-    // We only allow /vendor partition in debuggable Microdrod until it is verified during boot.
-    // TODO(b/285855436): remove this check.
-    if (IsMicrodroid()) {
-        bool mount_vendor =
-                cmdline.find("androidboot.microdroid.mount_vendor=1") != std::string::npos;
-        bool debuggable =
-                bootconfig.find("androidboot.microdroid.debuggable = \"1\"") != std::string::npos;
-        if (mount_vendor && !debuggable) {
-            LOG(FATAL) << "Attempted to mount /vendor partition for non-debuggable Microdroid VM";
-        }
-    }
-
     auto old_root_dir = std::unique_ptr<DIR, decltype(&closedir)>{opendir("/"), closedir};
     if (!old_root_dir) {
         PLOG(ERROR) << "Could not opendir(\"/\"), not freeing ramdisk";
diff --git a/init/first_stage_mount.cpp b/init/first_stage_mount.cpp
index c0b9281..ae216c6 100644
--- a/init/first_stage_mount.cpp
+++ b/init/first_stage_mount.cpp
@@ -16,6 +16,7 @@
 
 #include "first_stage_mount.h"
 
+#include <signal.h>
 #include <stdlib.h>
 #include <sys/mount.h>
 #include <unistd.h>
@@ -33,6 +34,7 @@
 #include <android-base/logging.h>
 #include <android-base/stringprintf.h>
 #include <android-base/strings.h>
+#include <android/avf_cc_flags.h>
 #include <fs_avb/fs_avb.h>
 #include <fs_mgr.h>
 #include <fs_mgr_dm_linear.h>
@@ -272,6 +274,11 @@
     return true;
 }
 
+// TODO: should this be in a library in packages/modules/Virtualization first_stage_init links?
+static bool IsMicrodroidStrictBoot() {
+    return access("/proc/device-tree/chosen/avf,strict-boot", F_OK) == 0;
+}
+
 bool FirstStageMountVBootV2::InitDevices() {
     std::set<std::string> devices;
     GetSuperDeviceName(&devices);
@@ -283,6 +290,14 @@
         return false;
     }
 
+    if (IsMicrodroid() && android::virtualization::IsOpenDiceChangesFlagEnabled()) {
+        if (IsMicrodroidStrictBoot()) {
+            if (!block_dev_init_.InitPlatformDevice("open-dice0")) {
+                return false;
+            }
+        }
+    }
+
     if (IsDmLinearEnabled()) {
         auto super_symlink = "/dev/block/by-name/"s + super_partition_name_;
         if (!android::base::Realpath(super_symlink, &super_path_)) {
@@ -381,9 +396,10 @@
     use_snapuserd_ = sm->IsSnapuserdRequired();
     if (use_snapuserd_) {
         if (sm->UpdateUsesUserSnapshots()) {
-            LaunchFirstStageSnapuserd(SnapshotDriver::DM_USER);
+            LaunchFirstStageSnapuserd();
         } else {
-            LaunchFirstStageSnapuserd(SnapshotDriver::DM_SNAPSHOT);
+            LOG(FATAL) << "legacy virtual-ab is no longer supported";
+            return false;
         }
     }
 
@@ -527,9 +543,48 @@
     return true;
 }
 
+static bool MaybeDeriveMicrodroidVendorDiceNode(Fstab* fstab) {
+    std::optional<std::string> microdroid_vendor_block_dev;
+    for (auto entry = fstab->begin(); entry != fstab->end(); entry++) {
+        if (entry->mount_point == "/vendor") {
+            microdroid_vendor_block_dev.emplace(entry->blk_device);
+            break;
+        }
+    }
+    if (!microdroid_vendor_block_dev.has_value()) {
+        LOG(VERBOSE) << "No microdroid vendor partition to mount";
+        return true;
+    }
+    // clang-format off
+    const std::array<const char*, 7> args = {
+        "/system/bin/derive_microdroid_vendor_dice_node",
+                "--dice-driver", "/dev/open-dice0",
+                "--microdroid-vendor-disk-image", microdroid_vendor_block_dev->data(),
+                "--output", "/microdroid_resources/dice_chain.raw",
+    };
+    // clang-format-on
+    // ForkExecveAndWaitForCompletion calls waitpid to wait for the fork-ed process to finish.
+    // The first_stage_console adds SA_NOCLDWAIT flag to the SIGCHLD handler, which means that
+    // waitpid will always return -ECHLD. Here we re-register a default handler, so that waitpid
+    // works.
+    LOG(INFO) << "Deriving dice node for microdroid vendor partition";
+    signal(SIGCHLD, SIG_DFL);
+    if (!ForkExecveAndWaitForCompletion(args[0], (char**)args.data())) {
+        LOG(ERROR) << "Failed to derive microdroid vendor dice node";
+        return false;
+    }
+    return true;
+}
+
 bool FirstStageMountVBootV2::MountPartitions() {
     if (!TrySwitchSystemAsRoot()) return false;
 
+    if (IsMicrodroid() && android::virtualization::IsOpenDiceChangesFlagEnabled()) {
+        if (!MaybeDeriveMicrodroidVendorDiceNode(&fstab_)) {
+            return false;
+        }
+    }
+
     if (!SkipMountingPartitions(&fstab_, true /* verbose */)) return false;
 
     for (auto current = fstab_.begin(); current != fstab_.end();) {
diff --git a/init/persistent_properties.cpp b/init/persistent_properties.cpp
index 6f8a4de..59e57b9 100644
--- a/init/persistent_properties.cpp
+++ b/init/persistent_properties.cpp
@@ -23,6 +23,7 @@
 #include <sys/types.h>
 
 #include <memory>
+#include <unordered_map>
 
 #include <android-base/file.h>
 #include <android-base/logging.h>
diff --git a/init/property_service.cpp b/init/property_service.cpp
index bc4ef42..58a0a7f 100644
--- a/init/property_service.cpp
+++ b/init/property_service.cpp
@@ -58,6 +58,7 @@
 #include <android-base/stringprintf.h>
 #include <android-base/strings.h>
 #include <fs_mgr.h>
+#include <private/android_filesystem_config.h>
 #include <property_info_parser/property_info_parser.h>
 #include <property_info_serializer/property_info_serializer.h>
 #include <selinux/android.h>
@@ -117,12 +118,13 @@
 
 static bool persistent_properties_loaded = false;
 
-static int property_set_fd = -1;
 static int from_init_socket = -1;
 static int init_socket = -1;
 static bool accept_messages = false;
 static std::mutex accept_messages_lock;
+static std::mutex selinux_check_access_lock;
 static std::thread property_service_thread;
+static std::thread property_service_for_system_thread;
 
 static std::unique_ptr<PersistWriteThread> persist_write_thread;
 
@@ -167,6 +169,7 @@
     ucred cr = {.pid = 0, .uid = 0, .gid = 0};
     audit_data.cr = &cr;
 
+    auto lock = std::lock_guard{selinux_check_access_lock};
     return selinux_check_access(source_context.c_str(), target_context, "file", "read",
                                 &audit_data) == 0;
 }
@@ -182,10 +185,9 @@
     audit_data.name = name.c_str();
     audit_data.cr = &cr;
 
-    bool has_access = (selinux_check_access(source_context, target_context, "property_service",
-                                            "set", &audit_data) == 0);
-
-    return has_access;
+    auto lock = std::lock_guard{selinux_check_access_lock};
+    return selinux_check_access(source_context, target_context, "property_service", "set",
+                                &audit_data) == 0;
 }
 
 void NotifyPropertyChange(const std::string& name, const std::string& value) {
@@ -400,30 +402,38 @@
         return {PROP_ERROR_INVALID_VALUE};
     }
 
-    prop_info* pi = (prop_info*)__system_property_find(name.c_str());
-    if (pi != nullptr) {
-        // ro.* properties are actually "write-once".
-        if (StartsWith(name, "ro.")) {
-            *error = "Read-only property was already set";
-            return {PROP_ERROR_READ_ONLY_PROPERTY};
-        }
-
-        __system_property_update(pi, value.c_str(), valuelen);
+    if (name == "sys.powerctl") {
+        // No action here - NotifyPropertyChange will trigger the appropriate action, and since this
+        // can come to the second thread, we mustn't call out to the __system_property_* functions
+        // which support multiple readers but only one mutator.
     } else {
-        int rc = __system_property_add(name.c_str(), name.size(), value.c_str(), valuelen);
-        if (rc < 0) {
-            *error = "__system_property_add failed";
-            return {PROP_ERROR_SET_FAILED};
-        }
-    }
+        prop_info* pi = (prop_info*)__system_property_find(name.c_str());
+        if (pi != nullptr) {
+            // ro.* properties are actually "write-once".
+            if (StartsWith(name, "ro.")) {
+                *error = "Read-only property was already set";
+                return {PROP_ERROR_READ_ONLY_PROPERTY};
+            }
 
-    bool need_persist = StartsWith(name, "persist.") || StartsWith(name, "next_boot.");
-    if (socket && persistent_properties_loaded && need_persist) {
-        if (persist_write_thread) {
-            persist_write_thread->Write(name, value, std::move(*socket));
-            return {};
+            __system_property_update(pi, value.c_str(), valuelen);
+        } else {
+            int rc = __system_property_add(name.c_str(), name.size(), value.c_str(), valuelen);
+            if (rc < 0) {
+                *error = "__system_property_add failed";
+                return {PROP_ERROR_SET_FAILED};
+            }
         }
-        WritePersistentProperty(name, value);
+
+        // Don't write properties to disk until after we have read all default
+        // properties to prevent them from being overwritten by default values.
+        bool need_persist = StartsWith(name, "persist.") || StartsWith(name, "next_boot.");
+        if (socket && persistent_properties_loaded && need_persist) {
+            if (persist_write_thread) {
+                persist_write_thread->Write(name, value, std::move(*socket));
+                return {};
+            }
+            WritePersistentProperty(name, value);
+        }
     }
 
     NotifyPropertyChange(name, value);
@@ -584,10 +594,10 @@
     return *ret;
 }
 
-static void handle_property_set_fd() {
+static void handle_property_set_fd(int fd) {
     static constexpr uint32_t kDefaultSocketTimeout = 2000; /* ms */
 
-    int s = accept4(property_set_fd, nullptr, nullptr, SOCK_CLOEXEC);
+    int s = accept4(fd, nullptr, nullptr, SOCK_CLOEXEC);
     if (s == -1) {
         return;
     }
@@ -1090,6 +1100,12 @@
     // required to support.
     constexpr auto VENDOR_API_LEVEL_PROP = "ro.vendor.api_level";
 
+    if (__system_property_find(VENDOR_API_LEVEL_PROP) != nullptr) {
+        // The device already have ro.vendor.api_level in its vendor/build.prop.
+        // Skip initializing the ro.vendor.api_level property.
+        return;
+    }
+
     auto vendor_api_level = GetIntProperty("ro.board.first_api_level", __ANDROID_VENDOR_API_MAX__);
     if (vendor_api_level != __ANDROID_VENDOR_API_MAX__) {
         // Update the vendor_api_level with "ro.board.api_level" only if both "ro.board.api_level"
@@ -1295,7 +1311,7 @@
     mkdir(APPCOMPAT_OVERRIDE_PROP_FOLDERNAME, S_IRWXU | S_IXGRP | S_IXOTH);
     if (!WriteStringToFile(serialized_contexts, APPCOMPAT_OVERRIDE_PROP_TREE_FILE, 0444, 0, 0,
                            false)) {
-        PLOG(ERROR) << "Unable to write vendor overrides to file";
+        PLOG(ERROR) << "Unable to write appcompat override property infos to file";
     }
     selinux_android_restorecon(APPCOMPAT_OVERRIDE_PROP_TREE_FILE, 0);
 }
@@ -1432,19 +1448,21 @@
     }
 }
 
-static void PropertyServiceThread() {
+static void PropertyServiceThread(int fd, bool listen_init) {
     Epoll epoll;
     if (auto result = epoll.Open(); !result.ok()) {
         LOG(FATAL) << result.error();
     }
 
-    if (auto result = epoll.RegisterHandler(property_set_fd, handle_property_set_fd);
+    if (auto result = epoll.RegisterHandler(fd, std::bind(handle_property_set_fd, fd));
         !result.ok()) {
         LOG(FATAL) << result.error();
     }
 
-    if (auto result = epoll.RegisterHandler(init_socket, HandleInitSocket); !result.ok()) {
-        LOG(FATAL) << result.error();
+    if (listen_init) {
+        if (auto result = epoll.RegisterHandler(init_socket, HandleInitSocket); !result.ok()) {
+            LOG(FATAL) << result.error();
+        }
     }
 
     while (true) {
@@ -1493,6 +1511,23 @@
     cv_.notify_all();
 }
 
+void StartThread(const char* name, int mode, int gid, std::thread& t, bool listen_init) {
+    int fd = -1;
+    if (auto result = CreateSocket(name, SOCK_STREAM | SOCK_CLOEXEC | SOCK_NONBLOCK,
+                                   /*passcred=*/false, /*should_listen=*/false, mode, /*uid=*/0,
+                                   /*gid=*/gid, /*socketcon=*/{});
+        result.ok()) {
+        fd = *result;
+    } else {
+        LOG(FATAL) << "start_property_service socket creation failed: " << result.error();
+    }
+
+    listen(fd, 8);
+
+    auto new_thread = std::thread(PropertyServiceThread, fd, listen_init);
+    t.swap(new_thread);
+}
+
 void StartPropertyService(int* epoll_socket) {
     InitPropertySet("ro.property_service.version", "2");
 
@@ -1504,19 +1539,9 @@
     init_socket = sockets[1];
     StartSendingMessages();
 
-    if (auto result = CreateSocket(PROP_SERVICE_NAME, SOCK_STREAM | SOCK_CLOEXEC | SOCK_NONBLOCK,
-                                   /*passcred=*/false, /*should_listen=*/false, 0666, /*uid=*/0,
-                                   /*gid=*/0, /*socketcon=*/{});
-        result.ok()) {
-        property_set_fd = *result;
-    } else {
-        LOG(FATAL) << "start_property_service socket creation failed: " << result.error();
-    }
-
-    listen(property_set_fd, 8);
-
-    auto new_thread = std::thread{PropertyServiceThread};
-    property_service_thread.swap(new_thread);
+    StartThread(PROP_SERVICE_FOR_SYSTEM_NAME, 0660, AID_SYSTEM, property_service_for_system_thread,
+                true);
+    StartThread(PROP_SERVICE_NAME, 0666, 0, property_service_thread, false);
 
     auto async_persist_writes =
             android::base::GetBoolProperty("ro.property_service.async_persist_writes", false);
diff --git a/init/reboot.cpp b/init/reboot.cpp
index 1a26c4d..150f8f4 100644
--- a/init/reboot.cpp
+++ b/init/reboot.cpp
@@ -1083,7 +1083,8 @@
                         return;
                     }
                 }
-            } else if (reboot_target == "quiescent") {
+            } else if (std::find(cmd_params.begin(), cmd_params.end(), "quiescent")
+                    != cmd_params.end()) { // Quiescent can be either subreason or details.
                 bootloader_message boot = {};
                 if (std::string err; !read_bootloader_message(&boot, &err)) {
                     LOG(ERROR) << "Failed to read bootloader message: " << err;
diff --git a/init/selinux.cpp b/init/selinux.cpp
index 1f211dd..e191b60 100644
--- a/init/selinux.cpp
+++ b/init/selinux.cpp
@@ -111,97 +111,6 @@
     return true;
 }
 
-// Forks, executes the provided program in the child, and waits for the completion in the parent.
-// Child's stderr is captured and logged using LOG(ERROR).
-bool ForkExecveAndWaitForCompletion(const char* filename, char* const argv[]) {
-    // Create a pipe used for redirecting child process's output.
-    // * pipe_fds[0] is the FD the parent will use for reading.
-    // * pipe_fds[1] is the FD the child will use for writing.
-    int pipe_fds[2];
-    if (pipe(pipe_fds) == -1) {
-        PLOG(ERROR) << "Failed to create pipe";
-        return false;
-    }
-
-    pid_t child_pid = fork();
-    if (child_pid == -1) {
-        PLOG(ERROR) << "Failed to fork for " << filename;
-        return false;
-    }
-
-    if (child_pid == 0) {
-        // fork succeeded -- this is executing in the child process
-
-        // Close the pipe FD not used by this process
-        close(pipe_fds[0]);
-
-        // Redirect stderr to the pipe FD provided by the parent
-        if (TEMP_FAILURE_RETRY(dup2(pipe_fds[1], STDERR_FILENO)) == -1) {
-            PLOG(ERROR) << "Failed to redirect stderr of " << filename;
-            _exit(127);
-            return false;
-        }
-        close(pipe_fds[1]);
-
-        if (execv(filename, argv) == -1) {
-            PLOG(ERROR) << "Failed to execve " << filename;
-            return false;
-        }
-        // Unreachable because execve will have succeeded and replaced this code
-        // with child process's code.
-        _exit(127);
-        return false;
-    } else {
-        // fork succeeded -- this is executing in the original/parent process
-
-        // Close the pipe FD not used by this process
-        close(pipe_fds[1]);
-
-        // Log the redirected output of the child process.
-        // It's unfortunate that there's no standard way to obtain an istream for a file descriptor.
-        // As a result, we're buffering all output and logging it in one go at the end of the
-        // invocation, instead of logging it as it comes in.
-        const int child_out_fd = pipe_fds[0];
-        std::string child_output;
-        if (!android::base::ReadFdToString(child_out_fd, &child_output)) {
-            PLOG(ERROR) << "Failed to capture full output of " << filename;
-        }
-        close(child_out_fd);
-        if (!child_output.empty()) {
-            // Log captured output, line by line, because LOG expects to be invoked for each line
-            std::istringstream in(child_output);
-            std::string line;
-            while (std::getline(in, line)) {
-                LOG(ERROR) << filename << ": " << line;
-            }
-        }
-
-        // Wait for child to terminate
-        int status;
-        if (TEMP_FAILURE_RETRY(waitpid(child_pid, &status, 0)) != child_pid) {
-            PLOG(ERROR) << "Failed to wait for " << filename;
-            return false;
-        }
-
-        if (WIFEXITED(status)) {
-            int status_code = WEXITSTATUS(status);
-            if (status_code == 0) {
-                return true;
-            } else {
-                LOG(ERROR) << filename << " exited with status " << status_code;
-            }
-        } else if (WIFSIGNALED(status)) {
-            LOG(ERROR) << filename << " killed by signal " << WTERMSIG(status);
-        } else if (WIFSTOPPED(status)) {
-            LOG(ERROR) << filename << " stopped by signal " << WSTOPSIG(status);
-        } else {
-            LOG(ERROR) << "waitpid for " << filename << " returned unexpected status: " << status;
-        }
-
-        return false;
-    }
-}
-
 bool ReadFirstLine(const char* file, std::string* line) {
     line->clear();
 
diff --git a/init/snapuserd_transition.cpp b/init/snapuserd_transition.cpp
index dea7af9..9e3ff41 100644
--- a/init/snapuserd_transition.cpp
+++ b/init/snapuserd_transition.cpp
@@ -62,7 +62,7 @@
 static constexpr char kSnapuserdLabel[] = "u:object_r:snapuserd_exec:s0";
 static constexpr char kSnapuserdSocketLabel[] = "u:object_r:snapuserd_socket:s0";
 
-void LaunchFirstStageSnapuserd(SnapshotDriver driver) {
+void LaunchFirstStageSnapuserd() {
     SocketDescriptor socket_desc;
     socket_desc.name = android::snapshot::kSnapuserdSocket;
     socket_desc.type = SOCK_STREAM;
@@ -85,22 +85,13 @@
     if (pid == 0) {
         socket->Publish();
 
-        if (driver == SnapshotDriver::DM_USER) {
-            char arg0[] = "/system/bin/snapuserd";
-            char arg1[] = "-user_snapshot";
-            char* const argv[] = {arg0, arg1, nullptr};
-            if (execv(arg0, argv) < 0) {
-                PLOG(FATAL) << "Cannot launch snapuserd; execv failed";
-            }
-            _exit(127);
-        } else {
-            char arg0[] = "/system/bin/snapuserd";
-            char* const argv[] = {arg0, nullptr};
-            if (execv(arg0, argv) < 0) {
-                PLOG(FATAL) << "Cannot launch snapuserd; execv failed";
-            }
-            _exit(127);
+        char arg0[] = "/system/bin/snapuserd";
+        char arg1[] = "-user_snapshot";
+        char* const argv[] = {arg0, arg1, nullptr};
+        if (execv(arg0, argv) < 0) {
+            PLOG(FATAL) << "Cannot launch snapuserd; execv failed";
         }
+        _exit(127);
     }
 
     auto client = SnapuserdClient::Connect(android::snapshot::kSnapuserdSocket, 10s);
diff --git a/init/snapuserd_transition.h b/init/snapuserd_transition.h
index 557d105..e86e8da 100644
--- a/init/snapuserd_transition.h
+++ b/init/snapuserd_transition.h
@@ -29,13 +29,8 @@
 namespace android {
 namespace init {
 
-enum class SnapshotDriver {
-    DM_SNAPSHOT,
-    DM_USER,
-};
-
 // Fork and exec a new copy of snapuserd.
-void LaunchFirstStageSnapuserd(SnapshotDriver driver);
+void LaunchFirstStageSnapuserd();
 
 class SnapuserdSelinuxHelper final {
     using SnapshotManager = android::snapshot::SnapshotManager;
diff --git a/init/test_kill_services/Android.bp b/init/test_kill_services/Android.bp
index 37361a8..ada87d8 100644
--- a/init/test_kill_services/Android.bp
+++ b/init/test_kill_services/Android.bp
@@ -10,7 +10,10 @@
 cc_test {
     name: "init_kill_services_test",
     srcs: ["init_kill_services_test.cpp"],
-    shared_libs: ["libbase"],
+    shared_libs: [
+        "libbase",
+        "libhidlbase",
+    ],
     test_suites: ["general-tests"],
 
     // TODO(b/153565474): switch back to auto-generation
diff --git a/init/test_kill_services/init_kill_services_test.cpp b/init/test_kill_services/init_kill_services_test.cpp
index 510ad8a..3af92bb 100644
--- a/init/test_kill_services/init_kill_services_test.cpp
+++ b/init/test_kill_services/init_kill_services_test.cpp
@@ -18,15 +18,20 @@
 
 #include <android-base/logging.h>
 #include <android-base/properties.h>
+#include <hidl/ServiceManagement.h>
 
 #include <iostream>
 
 using ::android::base::GetProperty;
 using ::android::base::SetProperty;
 using ::android::base::WaitForProperty;
+using ::android::hardware::isHidlSupported;
 using std::literals::chrono_literals::operator""s;
 
 void ExpectKillingServiceRecovers(const std::string& service_name) {
+    if (!isHidlSupported() && service_name == "hwservicemanager") {
+        GTEST_SKIP() << "No HIDL support on device so hwservicemanager will not be running";
+    }
     LOG(INFO) << "before we say hi to " << service_name << ", I can't have apexd around!";
 
     // b/280514080 - servicemanager will restart apexd, and apexd will restart the
diff --git a/init/util.cpp b/init/util.cpp
index e760a59..e5efc7d 100644
--- a/init/util.cpp
+++ b/init/util.cpp
@@ -27,6 +27,7 @@
 #include <string.h>
 #include <sys/socket.h>
 #include <sys/un.h>
+#include <sys/wait.h>
 #include <time.h>
 #include <unistd.h>
 
@@ -747,5 +748,96 @@
     return filtered_configs;
 }
 
+// Forks, executes the provided program in the child, and waits for the completion in the parent.
+// Child's stderr is captured and logged using LOG(ERROR).
+bool ForkExecveAndWaitForCompletion(const char* filename, char* const argv[]) {
+    // Create a pipe used for redirecting child process's output.
+    // * pipe_fds[0] is the FD the parent will use for reading.
+    // * pipe_fds[1] is the FD the child will use for writing.
+    int pipe_fds[2];
+    if (pipe(pipe_fds) == -1) {
+        PLOG(ERROR) << "Failed to create pipe";
+        return false;
+    }
+
+    pid_t child_pid = fork();
+    if (child_pid == -1) {
+        PLOG(ERROR) << "Failed to fork for " << filename;
+        return false;
+    }
+
+    if (child_pid == 0) {
+        // fork succeeded -- this is executing in the child process
+
+        // Close the pipe FD not used by this process
+        close(pipe_fds[0]);
+
+        // Redirect stderr to the pipe FD provided by the parent
+        if (TEMP_FAILURE_RETRY(dup2(pipe_fds[1], STDERR_FILENO)) == -1) {
+            PLOG(ERROR) << "Failed to redirect stderr of " << filename;
+            _exit(127);
+            return false;
+        }
+        close(pipe_fds[1]);
+
+        if (execv(filename, argv) == -1) {
+            PLOG(ERROR) << "Failed to execve " << filename;
+            return false;
+        }
+        // Unreachable because execve will have succeeded and replaced this code
+        // with child process's code.
+        _exit(127);
+        return false;
+    } else {
+        // fork succeeded -- this is executing in the original/parent process
+
+        // Close the pipe FD not used by this process
+        close(pipe_fds[1]);
+
+        // Log the redirected output of the child process.
+        // It's unfortunate that there's no standard way to obtain an istream for a file descriptor.
+        // As a result, we're buffering all output and logging it in one go at the end of the
+        // invocation, instead of logging it as it comes in.
+        const int child_out_fd = pipe_fds[0];
+        std::string child_output;
+        if (!android::base::ReadFdToString(child_out_fd, &child_output)) {
+            PLOG(ERROR) << "Failed to capture full output of " << filename;
+        }
+        close(child_out_fd);
+        if (!child_output.empty()) {
+            // Log captured output, line by line, because LOG expects to be invoked for each line
+            std::istringstream in(child_output);
+            std::string line;
+            while (std::getline(in, line)) {
+                LOG(ERROR) << filename << ": " << line;
+            }
+        }
+
+        // Wait for child to terminate
+        int status;
+        if (TEMP_FAILURE_RETRY(waitpid(child_pid, &status, 0)) != child_pid) {
+            PLOG(ERROR) << "Failed to wait for " << filename;
+            return false;
+        }
+
+        if (WIFEXITED(status)) {
+            int status_code = WEXITSTATUS(status);
+            if (status_code == 0) {
+                return true;
+            } else {
+                LOG(ERROR) << filename << " exited with status " << status_code;
+            }
+        } else if (WIFSIGNALED(status)) {
+            LOG(ERROR) << filename << " killed by signal " << WTERMSIG(status);
+        } else if (WIFSTOPPED(status)) {
+            LOG(ERROR) << filename << " stopped by signal " << WSTOPSIG(status);
+        } else {
+            LOG(ERROR) << "waitpid for " << filename << " returned unexpected status: " << status;
+        }
+
+        return false;
+    }
+}
+
 }  // namespace init
 }  // namespace android
diff --git a/init/util.h b/init/util.h
index 2d02182..aa24123 100644
--- a/init/util.h
+++ b/init/util.h
@@ -117,5 +117,10 @@
 // (.rc == .0rc for ranking purposes)
 std::vector<std::string> FilterVersionedConfigs(const std::vector<std::string>& configs,
                                                   int active_sdk);
+
+// Forks, executes the provided program in the child, and waits for the completion in the parent.
+// Child's stderr is captured and logged using LOG(ERROR).
+bool ForkExecveAndWaitForCompletion(const char* filename, char* const argv[]);
+
 }  // namespace init
 }  // namespace android
diff --git a/libcutils/Android.bp b/libcutils/Android.bp
index 8ae7d9e..b7752d9 100644
--- a/libcutils/Android.bp
+++ b/libcutils/Android.bp
@@ -116,27 +116,6 @@
     },
 }
 
-cc_test {
-    name: "libcutils_sockets_test",
-    test_suites: ["device-tests"],
-    static_libs: ["libbase", "libcutils_sockets"],
-    cflags: [
-        "-Wall",
-        "-Wextra",
-        "-Werror",
-    ],
-
-    srcs: ["sockets_test.cpp"],
-    target: {
-        android: {
-            srcs: [
-                "android_get_control_file_test.cpp",
-                "android_get_control_socket_test.cpp",
-            ],
-        },
-    },
-}
-
 // some files must not be compiled when building against Mingw
 // they correspond to features not used by our host development tools
 // which are also hard or even impossible to port to native Win32
@@ -347,7 +326,10 @@
 
 cc_test {
     name: "KernelLibcutilsTest",
-    test_suites: ["general-tests", "vts"],
+    test_suites: [
+        "general-tests",
+        "vts",
+    ],
     defaults: ["libcutils_test_static_defaults"],
     test_config: "KernelLibcutilsTest.xml",
 }
diff --git a/libcutils/abi-dumps/arm64/source-based/libcutils.so.lsdump b/libcutils/abi-dumps/arm64/source-based/libcutils.so.lsdump
index 333e61c..67c7514 100644
--- a/libcutils/abi-dumps/arm64/source-based/libcutils.so.lsdump
+++ b/libcutils/abi-dumps/arm64/source-based/libcutils.so.lsdump
@@ -290,6 +290,9 @@
    "name" : "fs_write_atomic_int"
   },
   {
+   "name" : "get_fs_config"
+  },
+  {
    "name" : "hashmapCreate"
   },
   {
@@ -1274,6 +1277,27 @@
    "source_file" : "system/core/libcutils/include/cutils/fs.h"
   },
   {
+   "function_name" : "get_fs_config",
+   "linker_set_key" : "get_fs_config",
+   "parameters" :
+   [
+    {
+     "referenced_type" : "_ZTIPKc"
+    },
+    {
+     "referenced_type" : "_ZTIb"
+    },
+    {
+     "referenced_type" : "_ZTIPKc"
+    },
+    {
+     "referenced_type" : "_ZTIP9fs_config"
+    }
+   ],
+   "return_type" : "_ZTIb",
+   "source_file" : "system/core/libcutils/include/private/fs_config.h"
+  },
+  {
    "function_name" : "hashmapCreate",
    "linker_set_key" : "hashmapCreate",
    "parameters" :
@@ -2392,6 +2416,15 @@
   },
   {
    "alignment" : 8,
+   "linker_set_key" : "_ZTIP9fs_config",
+   "name" : "fs_config *",
+   "referenced_type" : "_ZTI9fs_config",
+   "self_type" : "_ZTIP9fs_config",
+   "size" : 8,
+   "source_file" : "system/core/libcutils/include/private/fs_config.h"
+  },
+  {
+   "alignment" : 8,
    "linker_set_key" : "_ZTIP9str_parms",
    "name" : "str_parms *",
    "referenced_type" : "_ZTI9str_parms",
@@ -2684,6 +2717,37 @@
    "self_type" : "_ZTI5cnode",
    "size" : 40,
    "source_file" : "system/core/libcutils/include/cutils/config_utils.h"
+  },
+  {
+   "alignment" : 8,
+   "fields" :
+   [
+    {
+     "field_name" : "uid",
+     "referenced_type" : "_ZTIj"
+    },
+    {
+     "field_name" : "gid",
+     "field_offset" : 32,
+     "referenced_type" : "_ZTIj"
+    },
+    {
+     "field_name" : "mode",
+     "field_offset" : 64,
+     "referenced_type" : "_ZTIj"
+    },
+    {
+     "field_name" : "capabilities",
+     "field_offset" : 128,
+     "referenced_type" : "_ZTIm"
+    }
+   ],
+   "linker_set_key" : "_ZTI9fs_config",
+   "name" : "fs_config",
+   "referenced_type" : "_ZTI9fs_config",
+   "self_type" : "_ZTI9fs_config",
+   "size" : 24,
+   "source_file" : "system/core/libcutils/include/private/fs_config.h"
   }
  ],
  "rvalue_reference_types" : []
diff --git a/libcutils/abi-dumps/arm_arm64/source-based/libcutils.so.lsdump b/libcutils/abi-dumps/arm_arm64/source-based/libcutils.so.lsdump
index f612fb9..f75240c 100644
--- a/libcutils/abi-dumps/arm_arm64/source-based/libcutils.so.lsdump
+++ b/libcutils/abi-dumps/arm_arm64/source-based/libcutils.so.lsdump
@@ -300,6 +300,9 @@
    "name" : "fs_write_atomic_int"
   },
   {
+   "name" : "get_fs_config"
+  },
+  {
    "name" : "hashmapCreate"
   },
   {
@@ -1284,6 +1287,27 @@
    "source_file" : "system/core/libcutils/include/cutils/fs.h"
   },
   {
+   "function_name" : "get_fs_config",
+   "linker_set_key" : "get_fs_config",
+   "parameters" :
+   [
+    {
+     "referenced_type" : "_ZTIPKc"
+    },
+    {
+     "referenced_type" : "_ZTIb"
+    },
+    {
+     "referenced_type" : "_ZTIPKc"
+    },
+    {
+     "referenced_type" : "_ZTIP9fs_config"
+    }
+   ],
+   "return_type" : "_ZTIb",
+   "source_file" : "system/core/libcutils/include/private/fs_config.h"
+  },
+  {
    "function_name" : "hashmapCreate",
    "linker_set_key" : "hashmapCreate",
    "parameters" :
@@ -2402,6 +2426,15 @@
   },
   {
    "alignment" : 4,
+   "linker_set_key" : "_ZTIP9fs_config",
+   "name" : "fs_config *",
+   "referenced_type" : "_ZTI9fs_config",
+   "self_type" : "_ZTIP9fs_config",
+   "size" : 4,
+   "source_file" : "system/core/libcutils/include/private/fs_config.h"
+  },
+  {
+   "alignment" : 4,
    "linker_set_key" : "_ZTIP9str_parms",
    "name" : "str_parms *",
    "referenced_type" : "_ZTI9str_parms",
@@ -2694,6 +2727,37 @@
    "self_type" : "_ZTI5cnode",
    "size" : 20,
    "source_file" : "system/core/libcutils/include/cutils/config_utils.h"
+  },
+  {
+   "alignment" : 8,
+   "fields" :
+   [
+    {
+     "field_name" : "uid",
+     "referenced_type" : "_ZTIj"
+    },
+    {
+     "field_name" : "gid",
+     "field_offset" : 32,
+     "referenced_type" : "_ZTIj"
+    },
+    {
+     "field_name" : "mode",
+     "field_offset" : 64,
+     "referenced_type" : "_ZTIt"
+    },
+    {
+     "field_name" : "capabilities",
+     "field_offset" : 128,
+     "referenced_type" : "_ZTIy"
+    }
+   ],
+   "linker_set_key" : "_ZTI9fs_config",
+   "name" : "fs_config",
+   "referenced_type" : "_ZTI9fs_config",
+   "self_type" : "_ZTI9fs_config",
+   "size" : 24,
+   "source_file" : "system/core/libcutils/include/private/fs_config.h"
   }
  ],
  "rvalue_reference_types" : []
diff --git a/libcutils/ashmem-dev.cpp b/libcutils/ashmem-dev.cpp
index 410dbfd..46b8ef2 100644
--- a/libcutils/ashmem-dev.cpp
+++ b/libcutils/ashmem-dev.cpp
@@ -301,6 +301,12 @@
         return -1;
     }
 
+    // forbid size changes to match ashmem behaviour
+    if (fcntl(fd, F_ADD_SEALS, F_SEAL_GROW | F_SEAL_SHRINK) == -1) {
+        ALOGE("memfd_create(%s, %zd) F_ADD_SEALS failed: %m", name, size);
+        return -1;
+    }
+
     if (debug_log) {
         ALOGE("memfd_create(%s, %zd) success. fd=%d\n", name, size, fd.get());
     }
@@ -352,14 +358,29 @@
 }
 
 static int memfd_set_prot_region(int fd, int prot) {
-    /* Only proceed if an fd needs to be write-protected */
+    int seals = fcntl(fd, F_GET_SEALS);
+    if (seals == -1) {
+        ALOGE("memfd_set_prot_region(%d, %d): F_GET_SEALS failed: %s\n", fd, prot, strerror(errno));
+        return -1;
+    }
+
     if (prot & PROT_WRITE) {
+        /* Now we want the buffer to be read-write, let's check if the buffer
+         * has been previously marked as read-only before, if so return error
+         */
+        if (seals & F_SEAL_FUTURE_WRITE) {
+            ALOGE("memfd_set_prot_region(%d, %d): region is write protected\n", fd, prot);
+            errno = EINVAL;  // inline with ashmem error code, if already in
+                             // read-only mode
+            return -1;
+        }
         return 0;
     }
 
-    if (fcntl(fd, F_ADD_SEALS, F_SEAL_FUTURE_WRITE) == -1) {
-        ALOGE("memfd_set_prot_region(%d, %d): F_SEAL_FUTURE_WRITE seal failed: %s\n", fd, prot,
-              strerror(errno));
+    /* We would only allow read-only for any future file operations */
+    if (fcntl(fd, F_ADD_SEALS, F_SEAL_FUTURE_WRITE | F_SEAL_SEAL) == -1) {
+        ALOGE("memfd_set_prot_region(%d, %d): F_SEAL_FUTURE_WRITE | F_SEAL_SEAL seal failed: %s\n",
+              fd, prot, strerror(errno));
         return -1;
     }
 
diff --git a/libcutils/fs_config.cpp b/libcutils/fs_config.cpp
index 919be2f..5efe209 100644
--- a/libcutils/fs_config.cpp
+++ b/libcutils/fs_config.cpp
@@ -91,7 +91,7 @@
     { 00751, AID_ROOT,         AID_SHELL,        0, "vendor/bin" },
     { 00751, AID_ROOT,         AID_SHELL,        0, "vendor/apex/*/bin" },
     { 00755, AID_ROOT,         AID_SHELL,        0, "vendor" },
-    { 00755, AID_ROOT,         AID_ROOT,         0, 0 },
+    {},
         // clang-format on
 };
 #ifndef __ANDROID_VNDK__
@@ -218,17 +218,32 @@
     { 00640, AID_ROOT,      AID_SHELL,     0, "fstab.*" },
     { 00750, AID_ROOT,      AID_SHELL,     0, "init*" },
     { 00755, AID_ROOT,      AID_SHELL,     0, "odm/bin/*" },
+    { 00644, AID_ROOT,      AID_ROOT,      0, "odm/framework/*" },
+    { 00644, AID_ROOT,      AID_ROOT,      0, "odm/app/*" },
+    { 00644, AID_ROOT,      AID_ROOT,      0, "odm/priv-app/*" },
     { 00755, AID_ROOT,      AID_SHELL,     0, "product/bin/*" },
     { 00755, AID_ROOT,      AID_SHELL,     0, "product/apex/*bin/*" },
+    { 00644, AID_ROOT,      AID_ROOT,      0, "product/framework/*" },
+    { 00644, AID_ROOT,      AID_ROOT,      0, "product/app/*" },
+    { 00644, AID_ROOT,      AID_ROOT,      0, "product/priv-app/*" },
     { 00755, AID_ROOT,      AID_SHELL,     0, "system/bin/*" },
     { 00755, AID_ROOT,      AID_SHELL,     0, "system/xbin/*" },
     { 00755, AID_ROOT,      AID_SHELL,     0, "system/apex/*/bin/*" },
+    { 00644, AID_ROOT,      AID_ROOT,      0, "system/framework/*" },
+    { 00644, AID_ROOT,      AID_ROOT,      0, "system/app/*" },
+    { 00644, AID_ROOT,      AID_ROOT,      0, "system/priv-app/*" },
     { 00755, AID_ROOT,      AID_SHELL,     0, "system_ext/bin/*" },
     { 00755, AID_ROOT,      AID_SHELL,     0, "system_ext/apex/*/bin/*" },
+    { 00644, AID_ROOT,      AID_ROOT,      0, "system_ext/framework/*" },
+    { 00644, AID_ROOT,      AID_ROOT,      0, "system_ext/app/*" },
+    { 00644, AID_ROOT,      AID_ROOT,      0, "system_ext/priv-app/*" },
     { 00755, AID_ROOT,      AID_SHELL,     0, "vendor/bin/*" },
     { 00755, AID_ROOT,      AID_SHELL,     0, "vendor/apex/*bin/*" },
     { 00755, AID_ROOT,      AID_SHELL,     0, "vendor/xbin/*" },
-    { 00644, AID_ROOT,      AID_ROOT,      0, 0 },
+    { 00644, AID_ROOT,      AID_ROOT,      0, "vendor/framework/*" },
+    { 00644, AID_ROOT,      AID_ROOT,      0, "vendor/app/*" },
+    { 00644, AID_ROOT,      AID_ROOT,      0, "vendor/priv-app/*" },
+    {},
         // clang-format on
 };
 #ifndef __ANDROID_VNDK__
@@ -318,8 +333,8 @@
 auto __for_testing_only__fs_config_cmp = fs_config_cmp;
 #endif
 
-void fs_config(const char* path, int dir, const char* target_out_path, unsigned* uid, unsigned* gid,
-               unsigned* mode, uint64_t* capabilities) {
+bool get_fs_config(const char* path, bool dir, const char* target_out_path,
+                   struct fs_config* fs_conf) {
     const struct fs_path_config* pc;
     size_t which, plen;
 
@@ -362,11 +377,11 @@
             if (fs_config_cmp(dir, prefix, len, path, plen)) {
                 free(prefix);
                 close(fd);
-                *uid = header.uid;
-                *gid = header.gid;
-                *mode = (*mode & (~07777)) | header.mode;
-                *capabilities = header.capabilities;
-                return;
+                fs_conf->uid = header.uid;
+                fs_conf->gid = header.gid;
+                fs_conf->mode = header.mode;
+                fs_conf->capabilities = header.capabilities;
+                return true;
             }
             free(prefix);
         }
@@ -375,11 +390,28 @@
 
     for (pc = dir ? android_dirs : android_files; pc->prefix; pc++) {
         if (fs_config_cmp(dir, pc->prefix, strlen(pc->prefix), path, plen)) {
-            break;
+            fs_conf->uid = pc->uid;
+            fs_conf->gid = pc->gid;
+            fs_conf->mode = pc->mode;
+            fs_conf->capabilities = pc->capabilities;
+            return true;
         }
     }
-    *uid = pc->uid;
-    *gid = pc->gid;
-    *mode = (*mode & (~07777)) | pc->mode;
-    *capabilities = pc->capabilities;
+    return false;
+}
+
+void fs_config(const char* path, int dir, const char* target_out_path, unsigned* uid, unsigned* gid,
+               unsigned* mode, uint64_t* capabilities) {
+    struct fs_config conf;
+    if (get_fs_config(path, dir, target_out_path, &conf)) {
+        *uid = conf.uid;
+        *gid = conf.gid;
+        *mode = (*mode & S_IFMT) | conf.mode;
+        *capabilities = conf.capabilities;
+    } else {
+        *uid = AID_ROOT;
+        *gid = AID_ROOT;
+        *mode = (*mode & S_IFMT) | (dir ? 0755 : 0644);
+        *capabilities = 0;
+    }
 }
diff --git a/libcutils/include/private/fs_config.h b/libcutils/include/private/fs_config.h
index 45f46e5..9a727bc 100644
--- a/libcutils/include/private/fs_config.h
+++ b/libcutils/include/private/fs_config.h
@@ -21,8 +21,11 @@
 
 #pragma once
 
+#include <fcntl.h>
+#include <stdbool.h>
 #include <stdint.h>
 #include <sys/cdefs.h>
+#include <unistd.h>
 
 #include <linux/capability.h>
 
@@ -30,17 +33,27 @@
 
 __BEGIN_DECLS
 
-/*
- * Used in:
- *  build/tools/fs_config/fs_config.c
- *  build/tools/fs_get_stats/fs_get_stats.c
- *  system/extras/ext4_utils/make_ext4fs_main.c
- *  external/squashfs-tools/squashfs-tools/android.c
- *  system/core/cpio/mkbootfs.c
- *  system/core/adb/file_sync_service.cpp
- *  system/extras/ext4_utils/canned_fs_config.c
- */
+/* This API is deprecated. New users should call get_fs_config. */
 void fs_config(const char* path, int dir, const char* target_out_path, unsigned* uid, unsigned* gid,
                unsigned* mode, uint64_t* capabilities);
 
+struct fs_config {
+  uid_t uid;
+  gid_t gid;
+  mode_t mode;
+  uint64_t capabilities;
+};
+
+/*
+ * If a file system configuration was found for the specified path, store it to *conf.
+ * Returns whether a file system configuration was found.
+ *
+ * dir: Whether path refers to a directory.
+ * target_out_path: Path to the base directory to read the file system configuration from, or a null
+ * pointer to use the root directory as the base. Host code should pass $ANDROID_PRODUCT_OUT or
+ * equivalent, and device code should pass a null pointer.
+ */
+bool get_fs_config(const char* path, bool dir, const char* target_out_path,
+                   struct fs_config* conf);
+
 __END_DECLS
diff --git a/libmodprobe/Android.bp b/libmodprobe/Android.bp
index 1d94a96..12906cc 100644
--- a/libmodprobe/Android.bp
+++ b/libmodprobe/Android.bp
@@ -10,6 +10,7 @@
     vendor_available: true,
     ramdisk_available: true,
     recovery_available: true,
+    vendor_ramdisk_available: true,
     host_supported: true,
     srcs: [
         "libmodprobe.cpp",
diff --git a/libmodprobe/include/modprobe/modprobe.h b/libmodprobe/include/modprobe/modprobe.h
index 5d79d6a..d7a90c4 100644
--- a/libmodprobe/include/modprobe/modprobe.h
+++ b/libmodprobe/include/modprobe/modprobe.h
@@ -41,6 +41,7 @@
                             std::vector<std::string>* post_dependencies);
     void ResetModuleCount() { module_count_ = 0; }
     int GetModuleCount() { return module_count_; }
+    bool IsBlocklisted(const std::string& module_name);
 
   private:
     std::string MakeCanonical(const std::string& module_path);
@@ -52,7 +53,6 @@
     void AddOption(const std::string& module_name, const std::string& option_name,
                    const std::string& value);
     std::string GetKernelCmdline();
-    bool IsBlocklisted(const std::string& module_name);
 
     bool ParseDepCallback(const std::string& base_path, const std::vector<std::string>& args);
     bool ParseAliasCallback(const std::vector<std::string>& args);
diff --git a/libutils/CallStack.cpp b/libutils/CallStack.cpp
index fe827eb..029f4a7 100644
--- a/libutils/CallStack.cpp
+++ b/libutils/CallStack.cpp
@@ -89,7 +89,8 @@
 // The following four functions may be used via weak symbol references from libutils.
 // Clients assume that if any of these symbols are available, then deleteStack() is.
 
-#ifdef WEAKS_AVAILABLE
+// Apple and Windows does not support this, so only compile on other platforms.
+#if !defined(__APPLE__) && !defined(_WIN32)
 
 CallStack::CallStackUPtr CallStack::getCurrentInternal(int ignoreDepth) {
     CallStack::CallStackUPtr stack(new CallStack());
@@ -110,6 +111,6 @@
     delete stack;
 }
 
-#endif // WEAKS_AVAILABLE
+#endif  // !defined(__APPLE__) && !defined(_WIN32)
 
 }; // namespace android
diff --git a/libutils/CallStack_test.cpp b/libutils/CallStack_test.cpp
index 2cfaf61..7afc2c3 100644
--- a/libutils/CallStack_test.cpp
+++ b/libutils/CallStack_test.cpp
@@ -18,10 +18,16 @@
 
 #include <thread>
 
+#include <android-base/test_utils.h>
 #include <android-base/threads.h>
 #include <gtest/gtest.h>
 #include <utils/CallStack.h>
 
+#if defined(__ANDROID__)
+#include <log/log.h>
+#include <log/log_read.h>
+#endif
+
 __attribute__((__noinline__)) extern "C" void CurrentCaller(android::String8& backtrace) {
     android::CallStack cs;
     cs.update();
@@ -61,3 +67,38 @@
 
     ASSERT_NE(-1, cs.toString().find("(ThreadBusyWait")) << "Full backtrace:\n" << cs.toString();
 }
+
+#if defined(__ANDROID__)
+TEST(CallStackTest, log_stack) {
+    android::CallStack::logStack("callstack_test");
+    auto logger_list = android_logger_list_open(android_name_to_log_id("main"),
+                                                ANDROID_LOG_NONBLOCK, 1000, getpid());
+    ASSERT_NE(nullptr, logger_list);
+    std::string log;
+    while (true) {
+        log_msg log_msg;
+        auto ret = android_logger_list_read(logger_list, &log_msg);
+        if (ret == -EAGAIN) {
+            break;
+        }
+        ASSERT_GT(ret, 0);
+        if (log_msg.msg() == nullptr) {
+            continue;
+        }
+        // First get the tag.
+        char* msg = &log_msg.msg()[1];
+        if (std::string(msg) != "callstack_test") {
+            continue;
+        }
+        // Now move past the tag.
+        msg = &msg[strlen(msg) + 1];
+        log += msg;
+        log += '\n';
+    }
+    ASSERT_NE("", log) << "No messages found in the log from the test.";
+    // Look for a backtrace line such as:
+    //   #00 pc 00000000000536e4  libutils_test (testing::Test::Run()+436)
+    ASSERT_MATCH(log, "#\\d+ pc \\d+");
+    android_logger_list_close(logger_list);
+}
+#endif
diff --git a/libvendorsupport/include_llndk/android/llndk-versioning.h b/libvendorsupport/include_llndk/android/llndk-versioning.h
index 7c408c9..58cd18d 100644
--- a/libvendorsupport/include_llndk/android/llndk-versioning.h
+++ b/libvendorsupport/include_llndk/android/llndk-versioning.h
@@ -14,10 +14,9 @@
 
 #pragma once
 
-#include <sys/cdefs.h>
-
-__BEGIN_DECLS
-
+/* As a vendor default header included in all vendor modules, this header MUST NOT include other
+ * header files or any declarations. Only macros are allowed.
+ */
 #if defined(__ANDROID_VENDOR__)
 
 // LLNDK (https://source.android.com/docs/core/architecture/vndk/build-system#ll-ndk) is similar to
@@ -32,17 +31,26 @@
                     "call with '#if (__ANDROID_VENDOR_API__ >= " #vendor_api_level ")'."))) \
             _Pragma("clang diagnostic pop")
 
-// For the vendor libraries, __INTRODUCED_IN must be ignored because they are only for NDKs but not
-// for LLNDKs.
-#undef __INTRODUCED_IN
-#define __INTRODUCED_IN(x)
+// Use this macro as an `if` statement to call an API that are available to both NDK and LLNDK.
+// This returns true for the vendor modules if the vendor_api_level is less than or equal to the
+// ro.board.api_level.
+#define API_LEVEL_AT_LEAST(sdk_api_level, vendor_api_level) \
+    constexpr(__ANDROID_VENDOR_API__ >= vendor_api_level)
 
 #else  // __ANDROID_VENDOR__
 
-// For non-vendor libraries, __INTRODUCED_IN_LLNDK must be ignored because it must not change
-// symbols of NDK or the system side of the treble boundary.
-#define __INTRODUCED_IN_LLNDK(vendor_api_level)
+// __INTRODUCED_IN_LLNDK is for LLNDK only but not for NDK. Ignore this for non-vendor modules.
+// It leaves a no-op annotation for ABI analysis.
+#if !defined(__INTRODUCED_IN_LLNDK)
+#define __INTRODUCED_IN_LLNDK(vendor_api_level) \
+    __attribute__((annotate("introduced_in_llndk=" #vendor_api_level)))
+#endif
+
+// For non-vendor modules, API_LEVEL_AT_LEAST is replaced with __builtin_available(sdk_api_level) to
+// guard the API for __INTRODUCED_IN.
+#if !defined(API_LEVEL_AT_LEAST)
+#define API_LEVEL_AT_LEAST(sdk_api_level, vendor_api_level) \
+    (__builtin_available(android sdk_api_level, *))
+#endif
 
 #endif  // __ANDROID_VENDOR__
-
-__END_DECLS
diff --git a/rootdir/Android.bp b/rootdir/Android.bp
index c8a3cd6..6a3484e 100644
--- a/rootdir/Android.bp
+++ b/rootdir/Android.bp
@@ -71,3 +71,33 @@
     src: "adb_debug.prop",
     debug_ramdisk: true,
 }
+
+prebuilt_etc {
+    name: "init.zygote64.rc",
+    src: "init.zygote64.rc",
+    sub_dir: "init/hw",
+}
+
+prebuilt_etc {
+    name: "init.zygote32.rc",
+    src: "init.zygote32.rc",
+    sub_dir: "init/hw",
+}
+
+prebuilt_etc {
+    name: "init.zygote64_32.rc",
+    src: "init.zygote64_32.rc",
+    sub_dir: "init/hw",
+}
+
+prebuilt_etc {
+    name: "init.usb.rc",
+    src: "init.usb.rc",
+    sub_dir: "init/hw",
+}
+
+prebuilt_etc {
+    name: "init.usb.configfs.rc",
+    src: "init.usb.configfs.rc",
+    sub_dir: "init/hw",
+}
diff --git a/rootdir/Android.mk b/rootdir/Android.mk
index 7444f96..593bb1e 100644
--- a/rootdir/Android.mk
+++ b/rootdir/Android.mk
@@ -223,13 +223,6 @@
 	$(hide) sed -i -e 's?%EXPORT_GLOBAL_HWASAN_OPTIONS%?$(EXPORT_GLOBAL_HWASAN_OPTIONS)?g' $@
 	$(hide) sed -i -e 's?%EXPORT_GLOBAL_SCUDO_ALLOCATION_RING_BUFFER_SIZE%?$(EXPORT_GLOBAL_SCUDO_ALLOCATION_RING_BUFFER_SIZE)?g' $@
 
-# Append PLATFORM_VNDK_VERSION to base name.
-define append_vndk_version
-$(strip \
-  $(basename $(1)).$(PLATFORM_VNDK_VERSION)$(suffix $(1)) \
-)
-endef
-
 #######################################
 # sanitizer.libraries.txt
 include $(CLEAR_VARS)
diff --git a/rootdir/etc/linker.config.json b/rootdir/etc/linker.config.json
index d72ac66..61af6e9 100644
--- a/rootdir/etc/linker.config.json
+++ b/rootdir/etc/linker.config.json
@@ -32,6 +32,8 @@
   ],
   "provideLibs": [
     "libaptX_encoder.so",
-    "libaptXHD_encoder.so"
+    "libaptXHD_encoder.so",
+    "libEGL.so",
+    "libGLESv2.so"
   ]
 }
diff --git a/rootdir/init.rc b/rootdir/init.rc
index 8a2ed9f..d4cd4b8 100644
--- a/rootdir/init.rc
+++ b/rootdir/init.rc
@@ -247,6 +247,7 @@
     write /dev/blkio/background/blkio.bfq.weight 10
     write /dev/blkio/blkio.group_idle 0
     write /dev/blkio/background/blkio.group_idle 0
+    write /dev/blkio/blkio.prio.class promote-to-rt
     write /dev/blkio/background/blkio.prio.class restrict-to-be
 
     restorecon_recursive /mnt
@@ -303,6 +304,9 @@
     mkdir /mnt/runtime/full 0755 root root
     mkdir /mnt/runtime/full/self 0755 root root
 
+    # For Pre-reboot Dexopt
+    mkdir /mnt/pre_reboot_dexopt 0755 artd artd
+
     # Symlink to keep legacy apps working in multi-user world
     symlink /storage/self/primary /mnt/sdcard
     symlink /mnt/user/0/primary /mnt/runtime/default/self/primary
@@ -644,6 +648,8 @@
     mkdir /metadata/aconfig 0775 root system
     mkdir /metadata/aconfig/flags 0770 root system
     mkdir /metadata/aconfig/boot 0775 root system
+    exec_start aconfigd-init
+    start aconfigd
 
 on late-fs
     # Ensure that tracefs has the correct permissions.
@@ -853,6 +859,8 @@
     mkdir /data/misc/odsign 0710 root system
     # directory used for odsign metrics
     mkdir /data/misc/odsign/metrics 0770 root system
+    # directory used for connectivity blob store.
+    mkdir /data/misc/connectivityblobdb 0770 system system
 
     # Directory for VirtualizationService temporary image files.
     # Delete any stale files owned by the old virtualizationservice uid (b/230056726).
@@ -1358,3 +1366,16 @@
   write /sys/kernel/mm/lru_gen/enabled 5
 on property:persist.device_config.mglru_native.lru_gen_config=all
   write /sys/kernel/mm/lru_gen/enabled 7
+
+# Allow other processes to run `snapshotctl` through `init`. This requires
+# `set_prop` permission on `snapshotctl_prop`.
+on property:sys.snapshotctl.map=requested
+    # "root" is needed to talk to gsid and pass its check on uid.
+    # "system" is needed to write to "/dev/socket/snapuserd" to talk to
+    # snapuserd.
+    exec - root root system -- /system/bin/snapshotctl map
+    setprop sys.snapshotctl.map "finished"
+
+on property:sys.snapshotctl.unmap=requested
+    exec - root root system -- /system/bin/snapshotctl unmap
+    setprop sys.snapshotctl.unmap "finished"
diff --git a/toolbox/Android.bp b/toolbox/Android.bp
index 8594ec4..120cc6e 100644
--- a/toolbox/Android.bp
+++ b/toolbox/Android.bp
@@ -69,6 +69,7 @@
     name: "toolbox",
     defaults: ["toolbox_binary_defaults"],
     recovery_available: true,
+    vendor_ramdisk_available: true,
 }
 
 cc_binary {
diff --git a/toolbox/modprobe.cpp b/toolbox/modprobe.cpp
index 17d4e31..45dd9b8 100644
--- a/toolbox/modprobe.cpp
+++ b/toolbox/modprobe.cpp
@@ -112,6 +112,7 @@
     android::base::SetMinimumLogSeverity(android::base::INFO);
 
     std::vector<std::string> modules;
+    std::string modules_load_file;
     std::string module_parameters;
     std::string mods;
     std::vector<std::string> mod_dirs;
@@ -119,7 +120,7 @@
     bool blocklist = false;
     int rv = EXIT_SUCCESS;
 
-    int opt;
+    int opt, fd;
     int option_index = 0;
     // NB: We have non-standard short options -l and -D to make it easier for
     // OEMs to transition from toybox.
@@ -144,16 +145,19 @@
                 // is supported here by default, ignore flag if no argument.
                 check_mode();
                 if (optarg == NULL) break;
-                if (!android::base::ReadFileToString(optarg, &mods)) {
+
+                // Since libmodprobe doesn't fail when the modules load file
+                // doesn't exist, let's check that here so that we don't
+                // silently fail.
+                fd = open(optarg, O_RDONLY | O_CLOEXEC | O_BINARY);
+                if (fd == -1) {
                     PLOG(ERROR) << "Failed to open " << optarg;
-                    rv = EXIT_FAILURE;
+                    return EXIT_FAILURE;
                 }
-                for (auto mod : android::base::Split(stripComments(mods), "\n")) {
-                    mod = android::base::Trim(mod);
-                    if (mod == "") continue;
-                    if (std::find(modules.begin(), modules.end(), mod) != modules.end()) continue;
-                    modules.emplace_back(mod);
-                }
+                close(fd);
+
+                mod_dirs.emplace_back(android::base::Dirname(optarg));
+                modules_load_file = android::base::Basename(optarg);
                 break;
             case 'b':
                 blocklist = true;
@@ -233,30 +237,39 @@
     LOG(DEBUG) << "mode is " << mode;
     LOG(DEBUG) << "mod_dirs is: " << android::base::Join(mod_dirs, " ");
     LOG(DEBUG) << "modules is: " << android::base::Join(modules, " ");
+    LOG(DEBUG) << "modules load file is: " << modules_load_file;
     LOG(DEBUG) << "module parameters is: " << android::base::Join(module_parameters, " ");
 
     if (modules.empty()) {
         if (mode == ListModulesMode) {
             // emulate toybox modprobe list with no pattern (list all)
             modules.emplace_back("*");
-        } else {
+        } else if (modules_load_file.empty()) {
             LOG(ERROR) << "No modules given.";
             print_usage();
             return EXIT_FAILURE;
         }
     }
-    if (parameter_count && modules.size() > 1) {
+    if (parameter_count && (modules.size() > 1 || !modules_load_file.empty())) {
         LOG(ERROR) << "Only one module may be loaded when specifying module parameters.";
         print_usage();
         return EXIT_FAILURE;
     }
 
-    Modprobe m(mod_dirs, "modules.load", blocklist);
+    Modprobe m(mod_dirs, modules_load_file.empty() ? "modules.load" : modules_load_file, blocklist);
+    if (mode == AddModulesMode && !modules_load_file.empty()) {
+        if (!m.LoadListedModules(false)) {
+            PLOG(ERROR) << "Failed to load all the modules from " << modules_load_file;
+            return EXIT_FAILURE;
+        }
+        /* Fall-through to load modules provided on the command line (if any)*/
+    }
 
     for (const auto& module : modules) {
         switch (mode) {
             case AddModulesMode:
                 if (!m.LoadWithAliases(module, true, module_parameters)) {
+                    if (m.IsBlocklisted(module)) continue;
                     PLOG(ERROR) << "Failed to load module " << module;
                     rv = EXIT_FAILURE;
                 }
diff --git a/trusty/metrics/include/trusty/metrics/tipc.h b/trusty/metrics/include/trusty/metrics/tipc.h
index b29628e..e2cf57b 100644
--- a/trusty/metrics/include/trusty/metrics/tipc.h
+++ b/trusty/metrics/include/trusty/metrics/tipc.h
@@ -39,14 +39,17 @@
  * repository. They must be kept in sync.
  */
 
-#define METRICS_PORT "com.android.trusty.metrics"
+#define METRICS_PORT "com.android.trusty.metrics.consumer"
+
+#define UUID_STR_SIZE (37)
 
 /**
  * enum metrics_cmd - command identifiers for metrics interface
- * @METRICS_CMD_RESP_BIT:          message is a response
- * @METRICS_CMD_REQ_SHIFT:         number of bits used by @METRICS_CMD_RESP_BIT
- * @METRICS_CMD_REPORT_EVENT_DROP: report gaps in the event stream
- * @METRICS_CMD_REPORT_CRASH:      report an app crash event
+ * @METRICS_CMD_RESP_BIT:             message is a response
+ * @METRICS_CMD_REQ_SHIFT:            number of bits used by @METRICS_CMD_RESP_BIT
+ * @METRICS_CMD_REPORT_EVENT_DROP:    report gaps in the event stream
+ * @METRICS_CMD_REPORT_CRASH:         report an app crash event
+ * @METRICS_CMD_REPORT_STORAGE_ERROR: report trusty storage error
  */
 enum metrics_cmd {
     METRICS_CMD_RESP_BIT = 1,
@@ -54,6 +57,7 @@
 
     METRICS_CMD_REPORT_EVENT_DROP = (1 << METRICS_CMD_REQ_SHIFT),
     METRICS_CMD_REPORT_CRASH = (2 << METRICS_CMD_REQ_SHIFT),
+    METRICS_CMD_REPORT_STORAGE_ERROR = (3 << METRICS_CMD_REQ_SHIFT),
 };
 
 /**
@@ -90,17 +94,70 @@
 /**
  * struct metrics_report_crash_req - arguments of %METRICS_CMD_REPORT_CRASH
  *                                   requests
- * @app_id_len: length of app ID that follows this structure
+ * @app_id: uuid of the app that crashed
  * @crash_reason: architecture-specific code representing the reason for the
  *                crash
  */
 struct metrics_report_crash_req {
-    uint32_t app_id_len;
+    char app_id[UUID_STR_SIZE];
     uint32_t crash_reason;
 } __attribute__((__packed__));
 
-#define METRICS_MAX_APP_ID_LEN 256
+enum TrustyStorageErrorType {
+  TRUSTY_STORAGE_ERROR_UNKNOWN = 0,
+  TRUSTY_STORAGE_ERROR_SUPERBLOCK_INVALID = 1,
+  TRUSTY_STORAGE_ERROR_BLOCK_MAC_MISMATCH = 2,
+  TRUSTY_STORAGE_ERROR_BLOCK_HEADER_INVALID = 3,
+  TRUSTY_STORAGE_ERROR_RPMB_COUNTER_MISMATCH = 4,
+  TRUSTY_STORAGE_ERROR_RPMB_COUNTER_MISMATCH_RECOVERED = 5,
+  TRUSTY_STORAGE_ERROR_RPMB_COUNTER_READ_FAILURE = 6,
+  TRUSTY_STORAGE_ERROR_RPMB_MAC_MISMATCH = 7,
+  TRUSTY_STORAGE_ERROR_RPMB_ADDR_MISMATCH = 8,
+  TRUSTY_STORAGE_ERROR_RPMB_FAILURE_RESPONSE = 9,
+  TRUSTY_STORAGE_ERROR_RPMB_UNKNOWN = 10,
+  TRUSTY_STORAGE_ERROR_RPMB_SCSI_ERROR = 11,
+  TRUSTY_STORAGE_ERROR_IO_ERROR = 12,
+  TRUSTY_STORAGE_ERROR_PROXY_COMMUNICATION_FAILURE = 13,
+};
 
-#define METRICS_MAX_MSG_SIZE                                                \
-    (sizeof(struct metrics_req) + sizeof(struct metrics_report_crash_req) + \
-     METRICS_MAX_APP_ID_LEN)
+enum TrustyFileSystem {
+  TRUSTY_FS_UNKNOWN = 0,
+  TRUSTY_FS_TP = 1,
+  TRUSTY_FS_TD = 2,
+  TRUSTY_FS_TDP = 3,
+  TRUSTY_FS_TDEA = 4,
+  TRUSTY_FS_NSP = 5,
+};
+
+enum TrustyBlockType {
+  TRUSTY_BLOCKTYPE_UNKNOWN = 0,
+  TRUSTY_BLOCKTYPE_FILES_ROOT = 1,
+  TRUSTY_BLOCKTYPE_FREE_ROOT = 2,
+  TRUSTY_BLOCKTYPE_FILES_INTERNAL = 3,
+  TRUSTY_BLOCKTYPE_FREE_INTERNAL = 4,
+  TRUSTY_BLOCKTYPE_FILE_ENTRY = 5,
+  TRUSTY_BLOCKTYPE_FILE_BLOCK_MAP = 6,
+  TRUSTY_BLOCKTYPE_FILE_DATA = 7,
+  TRUSTY_BLOCKTYPE_CHECKPOINT_ROOT = 8,
+  TRUSTY_BLOCKTYPE_CHECKPOINT_FILES_ROOT = 9,
+  TRUSTY_BLOCKTYPE_CHECKPOINT_FREE_ROOT = 10,
+};
+
+struct metrics_report_storage_error_req {
+    enum TrustyStorageErrorType error;
+    char app_id[UUID_STR_SIZE];
+    char client_app_id[UUID_STR_SIZE];
+    uint32_t write;
+    enum TrustyFileSystem file_system;
+    uint64_t file_path_hash;
+    enum TrustyBlockType block_type;
+    uint64_t repair_counter;
+} __attribute__((__packed__));
+
+struct metrics_msg {
+    struct metrics_req req;
+    union {
+        struct metrics_report_crash_req crash_args;
+        struct metrics_report_storage_error_req storage_args;
+    };
+} __attribute__((__packed__));
\ No newline at end of file
diff --git a/trusty/metrics/metrics.cpp b/trusty/metrics/metrics.cpp
index 3ac128a..d2f0b0a 100644
--- a/trusty/metrics/metrics.cpp
+++ b/trusty/metrics/metrics.cpp
@@ -78,9 +78,8 @@
         return Error() << "connection to Metrics TA has not been initialized yet";
     }
 
-    uint8_t msg[METRICS_MAX_MSG_SIZE];
-
-    auto rc = read(metrics_fd_, msg, sizeof(msg));
+    struct metrics_msg metrics_msg;
+    int rc = read(metrics_fd_, &metrics_msg, sizeof(metrics_msg));
     if (rc < 0) {
         return ErrnoError() << "failed to read metrics message";
     }
@@ -89,23 +88,14 @@
     if (msg_len < sizeof(metrics_req)) {
         return Error() << "message too small: " << rc;
     }
-    auto req = reinterpret_cast<metrics_req*>(msg);
-    size_t offset = sizeof(metrics_req);
+    uint32_t cmd = metrics_msg.req.cmd;
     uint32_t status = METRICS_NO_ERROR;
 
-    switch (req->cmd) {
+    switch (cmd) {
         case METRICS_CMD_REPORT_CRASH: {
-            if (msg_len < offset + sizeof(metrics_report_crash_req)) {
-                return Error() << "message too small: " << rc;
-            }
-            auto crash_args = reinterpret_cast<metrics_report_crash_req*>(msg + offset);
-            offset += sizeof(metrics_report_crash_req);
-
-            if (msg_len < offset + crash_args->app_id_len) {
-                return Error() << "message too small: " << rc;
-            }
-            auto app_id_ptr = reinterpret_cast<char*>(msg + offset);
-            std::string app_id(app_id_ptr, crash_args->app_id_len);
+            struct metrics_report_crash_req crash_args = metrics_msg.crash_args;
+            auto app_id_ptr = crash_args.app_id;
+            std::string app_id(app_id_ptr, UUID_STR_SIZE);
 
             HandleCrash(app_id);
             break;
@@ -121,7 +111,7 @@
     }
 
     metrics_resp resp = {
-            .cmd = req->cmd | METRICS_CMD_RESP_BIT,
+            .cmd = cmd | METRICS_CMD_RESP_BIT,
             .status = status,
     };
 
diff --git a/trusty/utils/rpmb_dev/Android.bp b/trusty/utils/rpmb_dev/Android.bp
index a270087..5e9caaf 100644
--- a/trusty/utils/rpmb_dev/Android.bp
+++ b/trusty/utils/rpmb_dev/Android.bp
@@ -24,6 +24,7 @@
     ],
     shared_libs: [
         "libc",
+        "libcutils",
         "liblog",
         "libcrypto",
     ],
diff --git a/trusty/utils/rpmb_dev/rpmb_dev.c b/trusty/utils/rpmb_dev/rpmb_dev.c
index 0a9e6a1..cee3037 100644
--- a/trusty/utils/rpmb_dev/rpmb_dev.c
+++ b/trusty/utils/rpmb_dev/rpmb_dev.c
@@ -19,6 +19,7 @@
 #include "rpmb_protocol.h"
 
 #include <assert.h>
+#include <cutils/sockets.h>
 #include <errno.h>
 #include <fcntl.h>
 #include <getopt.h>
@@ -613,20 +614,24 @@
         return EXIT_FAILURE;
     }
 
-    cmdres_sock = socket(AF_UNIX, SOCK_STREAM, 0);
+    cmdres_sock = android_get_control_socket(socket_path);
     if (cmdres_sock < 0) {
-        ALOGE("rpmb_dev: Failed to create command/response socket: %s\n", strerror(errno));
-        return EXIT_FAILURE;
-    }
+        ALOGW("android_get_control_socket(%s) failed, fall back to create it\n", socket_path);
+        cmdres_sock = socket(AF_UNIX, SOCK_STREAM, 0);
+        if (cmdres_sock < 0) {
+            ALOGE("rpmb_dev: Failed to create command/response socket: %s\n", strerror(errno));
+            return EXIT_FAILURE;
+        }
 
-    cmdres_sockaddr.sun_family = AF_UNIX;
-    strncpy(cmdres_sockaddr.sun_path, socket_path, sizeof(cmdres_sockaddr.sun_path));
+        cmdres_sockaddr.sun_family = AF_UNIX;
+        strncpy(cmdres_sockaddr.sun_path, socket_path, sizeof(cmdres_sockaddr.sun_path));
 
-    ret = bind(cmdres_sock, (struct sockaddr*)&cmdres_sockaddr, sizeof(struct sockaddr_un));
-    if (ret < 0) {
-        ALOGE("rpmb_dev: Failed to bind command/response socket: %s: %s\n", socket_path,
-              strerror(errno));
-        return EXIT_FAILURE;
+        ret = bind(cmdres_sock, (struct sockaddr*)&cmdres_sockaddr, sizeof(struct sockaddr_un));
+        if (ret < 0) {
+            ALOGE("rpmb_dev: Failed to bind command/response socket: %s: %s\n", socket_path,
+                  strerror(errno));
+            return EXIT_FAILURE;
+        }
     }
 
     ret = listen(cmdres_sock, 1);
diff --git a/trusty/utils/rpmb_dev/rpmb_dev.rc b/trusty/utils/rpmb_dev/rpmb_dev.rc
index 9e203b8..33ec0f2 100644
--- a/trusty/utils/rpmb_dev/rpmb_dev.rc
+++ b/trusty/utils/rpmb_dev/rpmb_dev.rc
@@ -1,29 +1,34 @@
 # RPMB Mock
-on post-fs-data
-    mkdir /data/vendor/ss
-    chown root system /data/vendor/ss
-    chmod 0770 /data/vendor/ss
-    rm /data/vendor/ss/rpmb_sock
-    start rpmb_mock_init
+on post-fs
+    mkdir /mnt/vendor/persist/ss 0770 root system
+    exec_start rpmb_mock_init
     start rpmb_mock
 
+on post-fs-data
+    mkdir /data/vendor/ss 0770 root system
+    symlink /mnt/vendor/persist/ss /data/vendor/ss/persist
+    chown root system /data/vendor/ss/persist
+    chmod 0770 /data/vendor/ss/persist
+
     # Storage proxy
-    start storageproxyd
+    restart storageproxyd
 
-service storageproxyd /vendor/bin/storageproxyd -d /dev/trusty-ipc-dev0 \
-        -r /data/vendor/ss/rpmb_sock -p /data/vendor/ss -t sock
-    class main
-    disabled
-    user root
+service storageproxyd /vendor/bin/storageproxyd -d ${ro.hardware.trusty_ipc_dev:-/dev/trusty-ipc-dev0} \
+        -r /dev/socket/rpmb_mock -p /data/vendor/ss -t sock
+    class early_hal
+    user system
+    group system
 
-service rpmb_mock_init /vendor/bin/rpmb_dev --dev /data/vendor/ss/RPMB_DATA --init --size 2048
+service rpmb_mock_init /vendor/bin/rpmb_dev --dev /mnt/vendor/persist/ss/RPMB_DATA --init --size 2048
     disabled
     user system
     group system
     oneshot
 
-service rpmb_mock /vendor/bin/rpmb_dev --dev /data/vendor/ss/RPMB_DATA --sock /data/vendor/ss/rpmb_sock
+service rpmb_mock /vendor/bin/rpmb_dev --dev /mnt/vendor/persist/ss/RPMB_DATA \
+                          --sock rpmb_mock
     class main
     disabled
     user system
     group system
+    socket rpmb_mock stream 660 system system